Respiratory devices

ABSTRACT

Described here are devices for altering the flow of air in a respiratory cavity such as the mouth and nostrils of the nose. These methods and devices may be useful for affecting a physiologic benefit in patients suffering from a variety of medical diseases, particularly those that may benefit from “pursed-lip” breathing and non-invasive ventilation, such as COPD, heart failure, sleep apnea, and other medical disorders. The devices are typically removable devices that may be placed over or in a respiratory cavity to increase resistance to airflow within the respiratory cavity. Resistance to expiration may be selectively increased relative to inspiration. Removable oral and removable nasal devices are described. Oral and nasal devices that filter inhaled airflow of debris and allergens are also provided. A nasal device that increases patency of the nares is also provided.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.11/298,339, filed Dec. 8, 2005 entitled “RESPIRATORY DEVICES,” whichclaims the benefit under 35 U.S.C. 119 of U.S. Provisional PatentApplication No. 60/634,715, filed Dec. 8, 2004, titled “RESPIRATORYDEVICES AND METHODS OF USE.”

INCORPORATION BY REFERENCE

All publications and patent applications mentioned in this specificationare herein incorporated by reference to the same extent as if eachindividual publication or patent application was specifically andindividually indicated to be incorporated by reference.

FIELD OF THE INVENTION

The devices, methods, and kits described herein relate generally to thefield of medicine and more particularly to the fields of cardiovascularmedicine, sleep medicine, pulmonology, gastroenterology, and internalmedicine. In this regard, the devices, methods, and kits described maybe useful in the treatment of diseases including heart failure,hypertension, sleep apnea and other sleep disorders, snoring, chronicobstructive pulmonary disease (COPD), gastroesophageal reflux disease,and various inflammatory diseases, among others.

BACKGROUND OF THE INVENTION

Numerous disease states could benefit from the modification of patientrespiration, including heart failure, sleep apnea and other sleepdisorders, hypertension, snoring, chronic obstructive pulmonary disease(COPD), bronchitis, asthma, and many others.

Heart failure, or congestive heart failure (CHF), is a common clinicalsyndrome that represents the end-stage of a number of pulmonary andcardiac disease states. Heart failure is a degenerative condition thatoccurs when the heart muscle weakens and the ventricle no longercontracts normally. The heart can then no longer adequately pump bloodto the body including the lungs. This may lead to exercise intolerance,or may cause fluid retention with subsequent shortness of breath orswelling of the feet. Over four million people are diagnosed with heartfailure in the United States alone. Morbidity and mortality in patientswith heart failure is high.

Sleep apnea is defined as the temporary absence or cessation ofbreathing during sleep. Airflow must be absent for some period of timelonger than the usual inter-breath interval, typically defined as tenseconds for adults and eight seconds (or more than two times the normalrespiratory cycle time) for infants. There are three general varietiesof sleep apnea: central, obstructive, and mixed. In central sleep apnea,the patient makes no effort to breathe. In obstructive apnea,ventilatory effort is present, but no airflow results, because of upperairway closure. In mixed apnea, there is initially no ventilatory effort(suggestive of central sleep apnea), but an obstructive sleep apneapattern becomes evident when ventilatory effort resumes. Finally,hypopnea is a temporary decrease in inspiratory airflow that is out ofproportion to the individual's effort or metabolic needs. The termssleep apnea and/or sleep disordered breathing may refer to hypopnea.

Hypertension refers to elevated blood pressure, and is a very commondisease. Hypertension is characterized by elevated systolic and/ordiastolic blood pressures. Despite the prevalence of hypertension andits associated complications, control of the disease is far fromadequate. Only a third of people with hypertension control their bloodpressure adequately. This failure reflects the inherent problem ofmaintaining long-term therapy for a usually asymptomatic condition,particularly when the therapy may interfere with the patient's qualityof life, and when the immediate benefits of the therapy are not beobvious to the patient.

Chronic obstructive pulmonary disease (COPD) includes chronicbronchitis, emphysema and asthma. In both chronic bronchitis andemphysema, airflow obstruction limits the patient's airflow duringexhalation. COPD is a progressive disease characterized by a worseningbaseline respiratory status over a period of many years with sporadicexacerbations often requiring hospitalization. Early symptoms includeincreased sputum production and sporadic acute exacerbationscharacterized by increased cough, purulent sputum, wheezing, dyspnea,and fever. As the disease progresses, the acute exacerbations becomemore frequent. Late in the course of the disease, the patient maydevelop hypercapnia, hypoxemia, erythrocytosis, cor pulmonale withright-sided heart failure, and edema.

Chronic bronchitis is characterized by a chronic cough with sputumproduction leading to obstructed expiration. Pathologically, there maybe mucosal and submucosal edema and inflammation and an increase in thenumber and size of mucus glands. Emphysema is characterized bydestruction of the lung parenchyma leading to loss of elastic recoil,reduced tethering of airways, and obstruction to expiration.Pathologically, the distal airspaces are enlarged.

Asthma is another chronic lung condition, characterized by difficulty inbreathing. People with asthma have extra-sensitive or hyper-responsiveairways. The airways react by obstructing or narrowing when they becomeinflamed or irritated. This makes it difficult for the air to move inand out of the airways, leading to respiratory distress. This narrowingor obstruction can lead to coughing, wheezing, shortness of breath,and/or chest tightness. In some cases, asthma may be life threatening.

In all of these diseases, current medical and surgical therapies are notcompletely effective, and there is considerable room for improvement.Two therapies that are used to treat these diseases are pulmonaryrehabilitation (including pursed-lip breathing) and non-invasivemechanical ventilation.

Pulmonary rehabilitation is frequently used to treat patients sufferingfrom a variety of medical ailments such as those mentioned. For example,COPD patients are taught new breathing techniques that reducehyperinflation of the lungs and relieve expiratory airflow obstruction.One of the goals of this training is to reduce the level of dyspnea.Typically, these new breathing techniques include diaphragmatic andpursed-lip breathing. Pursed-lip breathing involves inhaling slowlythrough the nose and exhaling through pursed-lips (as if one werewhistling), taking two or three times as long to exhale as to inhale.Most COPD patients instinctively learn how to perform pursed-lipbreathing in order to relieve their dyspnea. Moreover, patients withasthma and other respiratory ailments, and even normal people duringexercise, have been shown to use pursed-lip breathing, especially duringtimes of exertion.

It is widely believed that producing a proximal obstruction (e.g.,pursing the lips) splints open the distal airways that have lost theirtethering in certain disease states. In other words, airways that wouldnormally collapse during respiration remain open when the patientbreathes through pursed-lips. Moreover, by increasing exhalation time,respiratory rate can be reduced and, in some cases, made more regular.

The medical literature has confirmed the utility of pursed-lip breathingin COPD patients. Specifically, it has been found that pursed-lipbreathing by COPD patients results in a reduction in respiratory rate,an increase in tidal volumes, and an improvement of oxygen saturation.All of these effects contribute to a reduction in patient dyspnea.However, pursed-lip breathing requires conscious effort. Thus, thepatient cannot breathe through pursed-lips while sleeping. As a result,the patient can still become hypoxic at night and may develop pulmonaryhypertension and other sequelae as a result. Furthermore, the patienthas to constantly regulate his own breathing. This interferes with hisperforming of other activities because the patient must pay attention tomaintaining pursed-lip breathing.

Non-invasive positive pressure ventilation (NPPV) is another method oftreating diseases that benefit from regulation of the patient'srespiration. NPPV refers to ventilation delivered by a nasal mask, nasalprongs/pillows or face mask. NPPV eliminates the need for intubation ortracheostomy. Outpatient methods of delivering NPPV include bilevelpositive airway pressure (BIPAP or bilevel) ventilator devices, orcontinuous positive airway pressure (CPAP) devices.

NPPV can deliver a set pressure during each respiratory cycle, with thepossibility of additional inspiratory pressure support in the case ofbi-level devices. NPPV has been shown to be very efficacious in suchdiseases as sleep apnea, heart failure, and COPD, and has becomeincreasingly used in recent years. Many patients use CPAP or BIPAP atnight while they are sleeping.

However, most patients experience difficulty adapting to nocturnal NPPV,leading to poor compliance. Mask discomfort is a very common problem forpatients new to NPPV, because of the high pressures on the nose, mouth,and face, and because of uncomfortably tight straps. Nasal congestionand dryness are also common complaints that may vary by season. Thenasal bridge can become red or ulcerated due to excessive mask tension.Eye irritation and acne can also result. Still other patients experienceabdominal distention and flatulence. Finally, air leakage through themouth is also very common in nasal NPPV patients, potentially leading tosleep arousals.

Both pursed-lip breathing and the use of NPPV have been shown to offersignificant clinical benefits to patients with a variety of medicalillnesses, including but not limited to COPD, heart failure, pulmonaryedema, sleep apnea (both central and obstructive) and other sleepdisordered breathing, cystic fibrosis, asthma, cardiac valve disease,arrhythmias, anxiety, and snoring. Expiratory resistance is believed toprovide the bulk of clinical improvements when using pursed-lipbreathing and NPPV, through a variety of physiologic mechanisms. Incontrast, inspiratory support is not believed to offer clinical benefitsin many patients. For example, in COPD, expiratory resistancefacilitates expiration, increases tidal volume, decreases respiratoryrate, and improves gas exchange. In the case of heart failure, it isfelt that positive pressure in the airways (due to expiratoryresistance) reduces pulmonary edema and improves lung compliance,decreases preload and afterload, increases pO₂, and decreases pCO₂. Inmany disease states, expiratory resistance helps maintain a more stablerespiratory rate that can have profound clinical effects to the patient.

It would therefore be desirable to have a medical device and/orprocedure that mimics the effect of pursed-lip breathing and/or thebenefits of non-invasive ventilation without suffering from thedrawbacks described above.

SUMMARY OF THE INVENTION

Described herein are respiratory devices and methods for treating avariety of medical diseases through the use of such devices. Someversions of these devices make use of expiratory resistance to mimic theeffects of pursed-lip breathing and non-invasive ventilation (with orwithout positive end expiratory pressure, or PEEP).

The respiratory device described herein is adapted to be removablysecured in communication with a respiratory cavity. A respiratory cavitymay be a nasal cavity (e.g., nostril or nasal passage) or an oral cavity(e.g., mouth or throat). The respiratory device comprises a passageway,an airflow resistor in communication with the passageway, and a holdfastfor removably securing the respiratory device in communication with therespiratory cavity. The airflow resistor alters the flow of air passingwithin the passageway. In particular, the airflow resistor may alter theflow of air within the passageway by increasing the resistance to theflow of air in the passageway. The respiratory device may be applied orremoved by the user of the device, and thus, does not need to be appliedby a physician or other healthcare personnel.

In one version, the respiratory device is adapted to be removablysecured in communication with a nasal cavity. The respiratory device mayalso comprise a rim for supporting the passageway. The rim may be, forexample, a frame, a framework, or a tube comprising a material and ashape that prevents the passageway from collapsing during use,particularly when the device is used during repeated cycles ofinhalation and exhalation. In some versions, the rim defines at least aportion of a wall of the passageway. However, the rim may support apassageway (or a portion of the passageway) which has another material(e.g., a medicinal or protective layer) that defines all or part of theinner lumen of the passageway.

In one version, the airflow resistor increases the resistance of airbeing exhaled and/or inhaled through the passageway. The airflowresistor may have an orientation, so that resistance to airflow in onedirection is greater than the opposite direction. For example, theairflow resistor may increase the resistance to air exhaled through thepassageway of the respiratory device without substantially increasingthe resistance to air inhaled through the passageway. The airflowresistor may increase the resistance to air exhaled through thepassageway of the respiratory device more than it increases theresistance to air inhaled through the passageway. Furthermore, therespiratory device may be reversible, so that in one orientationresistance to airflow through the device during inhalation is higherthan resistance to airflow through the device during exhalation. Byreversing the device (or by reversing the airflow resistor portion ofthe device), resistance to airflow through the device during exhalationis higher than resistance to airflow through the device duringinhalation.

In one version, the airflow resistor decreases the resistance to airexhaled and/or inhaled through the passageway when the airflow acrossthe airflow resistor or the air pressure differential across the airflowresistor exceeds a threshold level. Thus, for example, the respiratorydevice may not inhibit airflow (or not substantially inhibit airflow) inthe passageway during a cough, sneeze, nose blowing or other highairflow/high pressure event. The threshold value may be determined basedon measurements or approximations from a particular user. For example,the threshold may be a value above the normal peak of airflow orpressure during normal expiration. The threshold value may also bedetermined based on a typical value approximated from many patients Thisthreshold pressure for example may fall within the range of 0.1 to 1000cm H₂O pressure, more preferably within the range of 0.5 and 100 cm H₂Opressure, and most preferably within the range 1.0 and 50 cm H₂Opressure

In one version, the airflow resistor increases the resistance to airexhaled and/or inhaled through the passageway when the airflow acrossthe airflow resistor or the air pressure differential across the airflowresistor falls below a threshold level. Thus, the respiratory device maycreate a PEEP (positive end expiratory pressure) effect by, for example,preventing complete exhalation based on the pressure applied against thedevice, if the pressure and/or airflow at the end of exhalation arebelow the threshold level selected. The threshold level may correspondto an air pressure differential, air pressure, or airflow measured froman individual patient, or it may correspond to a typical value, such asa typical value measured from a sample of patients. This thresholdpressure for example may fall within the range of 0.1 to 150 cm H₂O,more preferably within the range of 0.5 to 30 cm H₂O, and mostpreferably within the range of 1.0 to 25 cm H₂0.

In some versions, the airflow resistor is a nested airflow resistor.Nested airflow resistors may be airflow resistors configured to alterthe flow of air in the passageway under different conditions (e.g.,different directions or different flow rates or pressure differentialsacross the resistor). For example, a nested airflow resistor may be acombination of multiple airflow resistors “nested” so that they affectthe flow of air in the passageway under different conditions. Thus afirst flap valve that increases the resistance to airflow in a firstdirection may be combined with a second flap valve that opens when theresistance to airflow in the first direction is above a threshold. Inone version, the second flap valve is integral to the flap portion ofthe first flap valve.

Virtually any type of airflow resistor may be used with the respiratorydevices described herein, including flap valves, membrane valves,hingeless valves, balloon valves, stopper-type valves, ball valves, andthe like. The device may include a variety of “one-way valvestructures,” or other flow responsive elements that open to inspirationand close partially or completely to expiration. In one version, theairflow resistor is a flap valve. The airflow resistor may be a platewhich is held within a nasal cavity that occludes some portion of theluminal cross-sectional area of the nasal cavity. The airflow resistormay selectively increase resistance to expiration while minimally ortrivially increasing flow resistance to inspiration. When closing duringexpiration, the airflow resistor may or may not fully prevent airflow,depending on the design of the device.

In one version, the airflow resistor is configured to alter theinspiratory time:expiratory time (I:E) ratio of a user wearing therespiratory device to be between about 3:1 and about 1:10. In anotherversion, the airflow resistor is configured to alter the inspiratorytime:expiratory time ratio of a user wearing the respiratory device tobe between about 1:1.5 and about 1:4. In another version, the airflowresistor is configured to alter the inspiratory time:expiratory timeratio of a user wearing the respiratory device to about 1:3.

In some versions of the respiratory device the holdfast removablysecures the respiratory device in communication with a nasal cavity of auser so that at least some of the air exchanged between the nasal cavityand the external environment of a user passes through the respiratorydevice. The holdfast may removably secure the respiratory device to auser's nasal cavity so that all of the air exchanged between the nasalcavity and the user's external environment passes through therespiratory device. The respiratory device may be secured at leastpartly within the nasal cavity, or totally within the nasal cavity, ortotally external to the nasal cavity, but in communication with thenasal cavity. The device may be adapted to communicate with the nasalcavity by being removably secured within or near the nares.

The respiratory device may be partly secured in the nasal cavity of auser so that an outer surface of the respiratory device exerts pressureagainst the nasal cavity. For example, an outer surface (e.g., theholdfast) may be oversized so that it exerts pressure against the nasalcavity.

In some versions of the respiratory device, the holdfast removablysecures the respiratory device in communication with both of a user'snasal cavities (e.g., both nostrils or nasal passages). In someversions, the holdfast may removably secure the respiratory devicewithin both of a user's nasal cavities (e.g., nostrils or nasalpassages). In some versions, the holdfast removably secures therespiratory device in communication with a user's oral cavity and atleast one nasal cavity.

In some versions, the respiratory device further comprises an activeagent. In some versions, this active agent is a drug (e.g., amedicament). In some versions, this active agent comprises an odorant,such as a fragrance. In some versions, the active agent comprisesmenthol, eucalyptus oil, and/or phenol.

In some versions, the respiratory device further comprises a filter.This filter may be a movable filter, such as a filter that filters airflowing through the passageway in one direction more than anotherdirection (e.g., the device may filter during inhalation but notexpiration).

In some versions, the respiratory device further comprises a respiratorygas supply. For example, a respiratory gas supply (e.g., Oxygen, or anymixture of respiratory gases) may be used in conjunction with arespiratory device. In some versions, the respiratory device is adaptedto connect to a respiratory gas supply.

In some versions, the holdfast comprises a conformable material. Forexample, the device may fit snugly within or against a respiratorycavity by compressing the holdfast (or a portion of the holdfast), whichmay expand to fit in or against the respiratory cavity securing thedevice in place, and preventing air exchange between the respiratorycavity and the external environment unless the air passes through therespiratory device.

Also described herein are respiratory devices adapted to removablysecure to a nasal cavity comprising a passageway, a rim, and a holdfastfor securing the respiratory device to at least one nasal cavity. Therim has sufficient strength to support the passageway in the open statewhen the device is inserted into the nasal cavity. The respiratorydevice may be applied or removed by the user.

Also described herein are respiratory devices adapted to be removablysecured in a nasal cavity comprising a passageway, a filter within thepassageway, and a holdfast for securing the respiratory device within anasal cavity. The respiratory device may be applied or removed by auser. In one version, the filter is a movable filter for filtering airflowing through the device during either inhalation (but not exhalation)or during exhalation (but not inhalation). For example, if the movablefilter filters air during inhalation, it may then move at least partlyout of the path of airflow during exhalation.

Also described herein are methods of regulating pCO₂ in a patientcomprising removably securing a respiratory device in communication witha patient's nasal cavity, wherein the respiratory device comprises anairflow resistor that inhibits expiration more than it inhibitsinhalation.

Also described herein are methods of simulating pursed-lip breathing inpatients comprising removably securing a respiratory device incommunication with a patient's nasal cavity, wherein the respiratorydevice comprises an airflow resistor that inhibits expiration more thanit inhibits inhalation.

Also described herein are methods of treating a sleeping disordercomprising removably securing a respiratory device in communication witha patient's nasal cavity, wherein the respiratory device comprises anairflow resistor that inhibits expiration more than it inhibitsinhalation.

Also described herein are methods of treating chronic obstructivepulmonary disease comprising removably securing a respiratory device incommunication with a patient's nasal cavity, wherein the respiratorydevice comprises an airflow resistor that inhibits expiration more thanit inhibits inhalation.

Also described herein are methods of treating a cardiovascular disordercomprising removably securing a respiratory device in communication witha patient's nasal cavity, wherein the respiratory device comprises anairflow resistor that inhibits expiration more than it inhibitsinhalation.

Also described herein are methods of treating a gastroenterologicdisorder (such as gastroesophageal reflux disease or hiatal hernia)comprising removably securing a respiratory device in communication witha patient's nasal cavity, wherein the respiratory device comprises anairflow resistor that inhibits expiration more than it inhibitsinhalation.

Also described herein are kits comprising a respiratory device asdescribed herein and instructions on the use of the respiratory device.

In some versions, the devices are removable and are placed within thenose and/or mouth of the patient.

In some versions of the respiratory device, the device is adapted to bein communication with an oral cavity by securing substantially withinthe oral cavity. The same embodiments described above for respiratorydevices that may be secured in communication with a nasal cavity may beused with these versions. The device may be substantially within theoral cavity when most (but not necessarily all) of the device is withinthe oral cavity. For example, a small portion of the device may projectfrom the oral cavity. Of course, in some variations, a device that issubstantially within the oral cavity may refer to a device that is heldentirely within the oral cavity.

Some of the devices feature either non-moving parts, or moving partsthat can partially obstruct the breathing passageway on expiration andminimally obstruct the breathing passageway on inspiration. That is, thedirection of the airflow and the pressure differential across the valvemay determine the degree of obstruction. The respiratory devices may beused during the day, night, or both. For example, these devices may beworn during sleep and/or during waking hours. Furthermore, the devicesmay be kept in place for long durations, such as several hours, days, orweeks.

The devices and methods described herein may be used to treat a varietyof disease states, and can be inserted and removed depending on need.These devices may also comprise a positioner to assist in positioningthe device in communication with a respiratory orifice such as the nasalcavities. The positioner may be attached to a device, for example, as ahandle or grip. The positioner may also be a device in which therespiratory device sits until it is secured in communication with arespiratory orifice, and then the positioner may be removed, leaving therespiratory device in place.

In some versions, the respiratory device comprises a nasal device usefulfor treating a variety of disease states. A user may conveniently insertand remove the device depending on need.

The methods for treating patients suffering from a variety of medicalailments through the use of an expiratory resistor broadly comprisecreating a resistance to expiratory flow in or around the oral and/ornasal cavities, typically within or around the mouth or the nares. Themethods may comprise use of any of the devices described above. Forexample, airflow resistance may be created by placing a flow resistor,either one with a fixed flow resistance or one with a variable flowresistance, i.e., which is higher to expiration than inspiration.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a respiratory device adapted for an oralcavity.

FIG. 2 is a perspective view of another respiratory device adapted forthe oral cavity.

FIG. 3 is a perspective view of the device shown in FIG. 2, where thedevice is positioned in a patient's oral cavity.

FIG. 4 shows a respiratory device adapted for the nasal cavity.

FIG. 5 shows a respiratory device adapted to fit substantially withinthe nasal cavity.

FIG. 6 shows a cross-sectional view of the device shown in FIG. 4, wherean airflow resistor is shown within the device.

FIGS. 7 a and 7 b show cross-sectional views of the device shown in FIG.4; FIG. 7 a shows the device during inhalation, and FIG. 7 b shows thedevice during exhalation.

FIGS. 8 a and 8 b are perspective views of a respiratory device showingan airflow resistor during exhalation (FIG. 8 a) and inhalation (FIG. 8b), respectively.

FIGS. 9 a and 9 b are perspective views of a respiratory device havingan airflow resistor where the airflow resistor is shown duringexhalation (FIG. 9 a) and inhalation (FIG. 9 b), respectively.

FIG. 10 is a perspective view of a respiratory device having an airflowresistor where the airflow resistor is shown during exhalation.

FIG. 11 is a perspective view of a respiratory device having an airflowresistor where the airflow resistor is shown during exhalation.

FIGS. 12 a and 12 b show cross-sectional views of the respiratorydevices shown in FIGS. 9 a, 9 b, 10, and 11 during exhalation (FIG. 12a) and inhalation (FIG. 12 b), respectively.

FIG. 12 c shows a cross-sectional view of a variation of the respiratorydevice during exhalation.

FIGS. 13 a and 13 b are perspective views of a respiratory device havingan airflow resistor where the airflow resistor is shown duringexhalation (FIG. 13 a) and inhalation (FIG. 13 b), respectively.

FIG. 14 is a perspective view of a respiratory device having an airflowresistor where the airflow resistor is shown during exhalation.

FIGS. 15 a, 15 b, and 15 c are perspective views of a respiratory devicehaving an airflow resistor. FIG. 15 a shows the airflow resistor duringhigher levels of exhalation airflow and/or pressure. FIG. 15 b shows theairflow resistor during lower levels of exhalation airflow and/orpressure. FIG. 15 c shows the airflow resistor during inhalation.

FIGS. 16 a and 16 b are perspective views of a respiratory device havingan airflow resistor where the airflow resistor is shown duringexhalation (FIG. 16 a) and inhalation (FIG. 16 b), respectively

FIGS. 17 a and 17 b are perspective views of a respiratory device havingan airflow resistor where the airflow resistor is shown duringexhalation (FIG. 17 a) and inhalation (FIG. 17 b), respectively.

FIGS. 18 a and 18 b show cross-sectional views of a respiratory devicehaving an airflow resistor where the airflow resistor is shown duringinhalation (FIG. 18 a) and exhalation (FIG. 18 b), respectively.

FIGS. 19 a and 19 b are cross-sectional views of a respiratory devicehaving an airflow resistor where the airflow resistor is shown duringlow pressure and/or low airflow exhalation (FIG. 19 a), and then duringhigh pressure and/or high airflow exhalation (FIG. 19 b).

FIG. 20 is a perspective view of a respiratory device where the deviceis removable and adapted for the nasal cavity.

FIG. 21 is a perspective view of a respiratory device where the deviceis removable and adapted for the nasal cavity.

FIG. 22 is a cross-sectional view of a respiratory device where thedevice is removable and adapted for the nasal cavity.

FIG. 23 is a cross-sectional view of a respiratory device where thedevice is removable and adapted for the nasal cavity.

FIG. 24 is a cross-sectional view of a respiratory device where thedevice is removable and adapted for the nasal cavity.

FIG. 25 is a cross-sectional view of a respiratory device where thedevice is removable and adapted for the nasal cavity.

FIGS. 26 a and 26 b are perspective views of a respiratory device havinga moveable air filter where the moveable air filter is shown duringinhalation (FIG. 26 a) and exhalation (FIG. 26 b), respectively.

FIG. 27 is a perspective view of another respiratory device where thedevice is removable and adapted for the nasal cavity.

FIG. 28 shows a cross-sectional view of another respiratory device wherethe device is removable and adapted for the nasal cavity.

FIG. 29 shows a schematic view of a kit including a respiratory devicein packaging and instructions for using the respiratory device.

DETAILED DESCRIPTION OF THE INVENTION

Described here are respiratory devices, kits, and methods for their usein improving respiratory and cardiovascular function. In general, therespiratory devices are referred to as respiratory devices or simply as“devices.” The devices and methods described herein may be useful totreat a variety of medical disease states, and may also be useful fornon-therapeutic purposes. The devices and methods described herein arenot limited to the particular embodiments described. Variations of theparticular embodiments may be made and still fall within the scope ofthe appended claims. It is also to be understood that the examples andparticular embodiments described are not intended to be limiting.Instead, the scope of the present invention will be established by theappended claims.

As used in this specification, the singular forms “a,” “an,” and “the”include plural reference unless the context clearly dictates otherwise.Unless defined otherwise, all technical and scientific terms used hereinhave the same meaning as commonly understood by one of ordinary skill inthe art.

Devices

The respiratory devices described herein alter airflow into and out ofthe lungs through a respiratory cavity such as the mouth and/or thenostrils of the nose. The respiratory devices typically include anairflow resistor capable of at least partly obstructing airflow,particularly airflow in one direction (e.g., expiration) more than theopposite direction (e.g., inhalation). In particular, the respiratorydevices may be used to increase the resistance to expiration during theexpiratory phase of the respiratory cycle. Many of the respiratorydevices described herein may prevent collapse of airways and airflowconduits, provide a method of drug delivery, and filter air ofundesirable compounds or agents.

Passageway

The respiratory devices described herein generally comprise an airflowpassageway and an airflow resistor. The airflow passageway (or“passageway”) generally defines a channel allowing the passage of air.The passageway may be of any suitable size or shape; however it isconfigured so that when the respiratory device is worn by a patient, thepassageway comprises an opening leading toward the patient's lungs influid connection with an opening that leads away from the patient'slungs. The term “patient” is used to describe any user of therespiratory device, including users who are not using the respiratorydevice for therapeutic purposes. The airflow passageway may be anysuitable length. For example, the passageway may be as short as theairflow resistor will allow (e.g., extending only enough to support theairflow resistor). Similarly, the airflow passageway may be longer thanthe space required to support the airflow resistor. For example, inversions of the respiratory device adapted for at least partialinsertion into a nasal cavity, the airflow passageway way may beapproximately as long as the length of an average nares. In someversions, the passageway extends the length of an average nasal chamber.

The neutral diameter of the passageway may be of any appropriate size.Neutral diameter refers to the diameter of the passageway when thedevice allows air to flow through the passageway without additionalresistance (e.g., due to an airflow resistor). In particular, thediameter of the passageway may depend upon configuration of therespiratory device. For example, respiratory devices configured to beinserted within the nasal cavity (e.g., a nasal chamber) may have adiameter that is approximately the diameter of a narrow portion of thenasal cavity, or slightly narrower. Respiratory devices configured to besecured over an oral cavity or a nasal cavity may have passageways oflarger diameters. Furthermore, the diameter of a passageway may varyacross the length of the device.

The airflow passageway may comprise a dedicated structure defining theinner wall of the airflow passageway, or it may be a structuralcomponent of the device. For example, the passageway may comprise apassage wall defined by a rim. A rim may be a tube (or tunnel) ofmaterial of any appropriate thickness. The rim may also be a frame,rather than a complete tube. The rim may comprise a sufficiently rigidmaterial so that it can support the passageway, and prevent thepassageway from collapsing during use and during respiration. In someversions, the rim comprises a compressible material that may becompressed to facilitate insertion and removal, while maintaining theability to support the passageway and prevent complete collapse of thepassageway during respiration. The rim may also be somewhat compressibleduring respiratory flow. The airflow passageway (including a rimportion) may also serve as an attachment site for other components suchas airflow resistors, filters, anchors, etc.

The rim may be any suitable shape or size. For example, the rim maycomprise a ring shape or an oval shape. The rim may have an innerdiameter which is equivalent to (or larger than) the diameter of thepassageway. In some versions, the rim comprises a material havingstrength sufficient to prevent the collapse of a respiratory device thathas been inserted into a nasal cavity. For example, the rim may comprisea metal, a polymer (particularly stiff polymers), etc. In some versions,the rim may comprise softer or “weaker” materials which are formed orarranged so that the final shape of the rim has sufficient strength toprevent the collapse of the respiratory device during use.

In some versions, the airflow passageway does not include a dedicatedstructure such as a rim. For example, the airflow passageway of therespiratory device may be a passageway through another component of thedevice, such as holdfast. In some versions, the airflow passageway isdefined by a passageway through a holdfast.

Airflow Resistor

An airflow resistor is typically positioned in communication with atleast one airflow passageway, so that at least some of the air flowingthrough the passageway passes the airflow resistor. Thus, an airflowresistor modulates, alters, varies, or keeps constant the amount ofresistance, the degree of airflow, or the pressure differential acrossthe device or through a passageway in the device. In some versions, theairflow resistor inhibits airflow more greatly in one direction than theopposite direction. Thus, the airflow resistor may regulate airflow toand from the lungs. Some versions of the device have a greaterresistance to exhalation than to inhalation during use.

In some versions of the respiratory device, the airflow resistorcomprises a valve that does not appreciably impede airflow in a certaindirection (e.g., inspiration), and that partially or completely impedesairflow in the other direction (e.g., expiration). In some embodiments,the valve allows for an expiratory obstruction to be relieved if acertain degree of airflow or pressure differential across the device isachieved, as might be the case with coughing or nose blowing. Forexample, in some embodiments, the valve comprises a flap made of a shapememory or deformable material (e.g., an elastic material); when thepressure differential across the valve (the expiratory airflow pressure)is large enough, the flap bends upon itself, thereby relieving theobstruction. This may be important during coughing and may alsofacilitate the clearance of mucous and other substances during coughing.After the cough, the flap returns to its original, non-bentconformation.

Examples of different types of airflow resistors are described below andillustrated in FIGS. 6, 8, 9, 10, 11, and 13-19. Any airflow resistancedevice capable of altering the resistance of air (e.g., due toinspiration and/or expiration) passing through an air passageway may beused, particularly devices which selectively increase the resistance ofair flow in one direction more than in the opposite direction.Valve-type airflow resistors are particularly suitable. Examples ofvalves which may be used as airflow resistors include: flap valves(having one or more flaps); hingeless valves; stopper-type valves;membrane-type valves; ball valves; balloon-type valves; and the like.This list is not intended to be exhaustive, and other types of selectiveairflow resistors may be used. Moreover, multiple airflow resistors mayalso be used, which may include combinations of different types ofairflow resistors.

Holdfast

The respiratory device may further comprise a holdfast for releasablysecuring the device in communication with a nasal and/or oral cavity.The holdfast may facilitate the positioning and securing of the devicein a desired location, such as over or within (e.g., substantiallywithin) a respiratory orifice. In particular, the holdfast may allow thedevice to be anchored, positioned, and/or stabilized in any locationthat is subject to respiratory airflow such as a respiratory cavity.

Examples of respiratory cavities include nasal and oral cavities. Nasalcavities may comprise the nostrils, nares or nasal chambers, limen,vestibule, greater alar cartilage, alar fibrofatty tissue, lateral nasalcartilage, agger nasi, floor of the nasal cavity, turbinates, sinuses(frontal, ethmoid, sphenoid, and maxillary), and nasal septum. The term“nasal cavity” may refer to any sub-region of the Nasal Fossa (e.g., asingle nostril, nare, or nasal chamber).

An oral cavity includes the cavity of the mouth (e.g., vestibule andmouth cavity proper), and any sub-region thereof, including or more thanone of the following structures: maxilla, mandible, gums, lips, teeth,jaw, tongue, hard or soft palate and the recess or gap between theteeth/gums and the lips.

In some versions, the holdfast may also secure a seal between therespiratory device and the respiratory airway, so that at least some ofthe air exchanged between the outside of the patient and the respiratoryairway must pass through the respiratory device. In some versions, theholdfast seals the device in communication with a respiratory cavitycompletely, so that all air must be exchanged through the device. Insome versions, the holdfast seal is incomplete, so that only some of theair exchanged between the patient and the external environment passesthrough the device. As used herein, “air” may be air from environmentexternal to the patient, or it may be any respiratory gas (e.g., pure ormixed oxygen, CO₂, heliox, or other gas mixtures provided to the user).

In some versions, the holdfast may comprise an anchor or anchor region.

In some embodiments, the device is to be placed by the patient or thehealthcare provider in communication with an oral cavity. In this case,the holdfast may comprise any suitable mechanism for securing the devicein position in communication with an oral cavity. The holdfast maycomprise insertive (e.g., mouthpiece-type) and non-insertive mechanisms.A non-insertive holdfast may comprise a surface configured to mate withthe outer surface of a patient's face to secure the device. For example,a holdfast may comprise an adhesive bandage, a strap, or any otherstructure capable of securing the device in communication with a user'srespiratory cavity. The holdfast may comprise a removable region thatcontours to interfaces with the lips, gums, teeth, tongue and/or softpalate of the user, allowing the user to insert or remove the device asneeded. Alternatively, the device can be held in place by utilizing thearea in between the gums and teeth or lips.

In other embodiments, the device is to be placed by the patient or thehealthcare provider in or around the nasal cavity. Holdfasts appropriatefor nasal cavities may secure the device in position within a nasalcavity (e.g., through one or both nostrils) or against surroundingstructures. The holdfast may comprise a shape, surface or material thatsecures the device in communication with a nasal cavity. For example,the holdfast may comprise a cylindrical shape that allows the device tofit securely or snugly within a nostril. The outer surface of the devicemay comprise a holdfast including an adhesive material. In addition toholding the device in place, the holdfast may also partially orcompletely seal the device in communication with the nasal cavity. Theholdfast may comprise insertive and/or non-insertive mechanisms. In someversions, the holdfast comprises a mechanical connection between thedevice and the user, such as a clips, straps, and the like.

The holdfast may be formed from a soft or compliant material thatprovides a seal, and may enhance patient comfort. Furthermore, compliantmaterials may reduce the likelihood that the device cuts off blood flowto the part of the respiratory cavity and surrounding regions (mouth ornose) to which the device is anchored. This compliant material may beone of a variety of materials including, but not limited to, plastic,polymers, cloth, foamed, spongy, or shape memory materials. Shapematerials include any that have a preferred conformation, and afterbeing deformed or otherwise deflected or altered in shape, have tendencyto return to a preferred conformation. Soft shape memory materials mayinclude, but are not limited to, urethane, polyurethane, sponge, andothers (including “foamed” versions of these materials). Alternatively,the holdfast may not be soft or compliant and may instead be a rigidstructure that interfaces directly with the respiratory orifice. Forexample, in versions of the respiratory device configured to be used atleast partly within a nasal cavity, it is understood that the device mayfit completely within a nostril (or both nostrils), or may project outof the nostril, depending on the particular embodiment. In some cases,the device may be placed high enough within the nasal cavity so that itcannot be seen within the nostril. In some embodiments the device may belocated completely outside of the nose, for example, in some versionsthe holdfast has a shape that conforms to the outside surface of thenose. Thus, the holdfast may comprise one or more straps, bands, or thelike to ensure an adequate fit and/or seal maintaining the device incommunication with the nasal cavity. In another embodiment the holdfastmay comprise one or more projections that are inserted within thenostrils. In some versions, a device may be placed at least partly inboth nostrils, and may comprise a bifurcated passageway or twopassageways that the holdfast places in communication with the nasalcavity through each nostril. In this case, the inspiratory and/orexpiratory airflow to and from the lungs may be regulated through eachnostril separately or together. In some versions, separate devices maybe placed at least partly in each nostril, and may be connected to eachother and/or the patient using a clip, tether, strap, band, chain,string, or the like. Such a system would facilitate subsequent removalof the device and make migration of the devices deeper into the nasalcavity less likely. Finally, in some devices, an adhesive flap may bepresent to help attach the device to the inside or outside of the nose(including the nostrils), to the oral cavity, to the neck, or to theface.

Materials

Respiratory devices may be made from any appropriate material ormaterials. In certain embodiments, the devices include a shape memoryelement or elements, as part of the holdfast, in the airflow resistor,or in giving form to the passageway. Any convenient shape memorymaterial that provides for flexibility and resumption of configurationfollowing removal of applied force may be employed in these embodiments.For example, shape memory alloys may be used. A variety of shape memoryalloys are known, including those described in U.S. Pat. Nos. 5,876,434;5,797,920; 5,782,896; 5,763,979; 5,562,641; 5,459,544; 5,415,660;5,092,781; 4,984,581; the disclosures of which are herein incorporatedby reference in their entirety. The shape memory alloy that is employedshould generally be a biocompatible alloy. Biocompatible alloys mayinclude nickel-titanium (NiTi) shape memory alloys sold under theNitinol™ name by Memry Corporation (Brookfield, Conn.). Also of interestare spring steel and shape memory polymeric or plastic materials, suchas polypropylene, polyethylene, etc.

Rubber and polymeric materials may also be used, particularly for theholdfast or airflow resistor. For example, materials which may be usedinclude: latex, polyethylene, polypropylene, polystyrene, polyvinylchloride, polyvinylidene chloride, polyvinyl acetate, polyacrylate,styrene-butadiene copolymer, chlorinated polyethylene, polyvinylidenefluoride, ethylene-vinyl acetate copolymer, ethylene-vinyl acetate-vinylchloride-acrylate copolymer, ethylene-vinyl acetate-acrylate copolymer,ethylene-vinyl acetate-vinyl chloride copolymer, nylon,acrylonitrile-butadiene copolymer, polyacrylonitrile, polyvinylchloride, polychloroprene, polybutadiene, thermoplastic polyimide,polyacetal, polyphenylene sulfide, polycarbonate, thermoplasticpolyurethane, thermoplastic resins, thermosetting resins, naturalrubbers, synthetic rubbers (such as a chloroprene rubber, styrenebutadiene rubber, nitrile-butadiene rubber, and ethylene-propylene-dieneterpolymer copolymer, silicone rubbers, fluoride rubbers, and acrylicrubbers), elastomers (such as a soft urethane, water-blownpolyurethane), and thermosetting resins (such as a hard urethane,phenolic resins, and a melamine resins).

Biocompatible materials may be used, particularly for those portions ofthe device (e.g., the holdfast) which may contact a user. In addition tosome of the materials described above, the biocompatible materials mayalso include a biocompatible polymer and/or elastomer. Suitablebiocompatible polymers may include materials such as: a homopolymer andcopolymers of vinyl acetate (such as ethylene vinyl acetate copolymerand polyvinylchloride copolymers), a homopolymer and copolymers ofacrylates (such as polypropylene, polymethylmethacrylate,polyethylmethacrylate, polymethacrylate, ethylene glycol dimethacrylate,ethylene dimethacrylate and hydroxymethyl methacrylate, and the like),polyvinylpyrrolidone, 2-pyrrolidone, polyacrylonitrile butadiene,polyamides, fluoropolymers (such as polytetrafluoroethylene andpolyvinyl fluoride), a homopolymer and copolymers of styreneacrylonitrile, cellulose acetate, a homopolymer and copolymers ofacrylonitrile butadiene styrene, polymethylpentene, polysulfonespolyimides, polyisobutylene, polymethylstyrene and other similarcompounds known to those skilled in the art.

Other materials of interest include any materials that can serve asfilters for allergens, pollen, dander, smog, etc. By providing a filterwithin the device, sinusitis, sleep apnea, snoring, hay fever, allergicrhinitis, and other allergic respiratory conditions may be reduced orprevented. This filter may in fact be part of the airflow resistor ormay be a separate component of the device. Any suitable filteringmaterial known to those skilled in the art may be used with therespiratory devices described herein. Such materials include, but arenot limited to, activated carbon charcoal filters, hollow-fiber filters,and the like.

In some versions, the respiratory device may comprise a filter thatremains in the path of inhalation and/or exhalation during use. In someversions, the filter material remains in the path of both inspiratoryand expiratory airflow. This filter material may not appreciably alterresistance to airflow in either direction, or it may alter airflow tosubstantially the same degree in both directions (inhalation andexhalation). In some versions, the filter comprises a material having alarge pore size so that airflow is not significantly inhibited.

Operation of the Respiratory Device

The airflow resistor may be oriented in any direction. For example, insome embodiments of the device, the airflow resistor comprises valveflaps that are oriented such that both flaps are in a closed positionduring inspiration and in an open position during expiration. Therespiratory devices may be orientated so that the airflow resistorincreases resistance to expiration, and has a relatively lower ornegligible resistance to inspiration. However, these devices can beoriented in the opposite direction as well, so that the device offersincreased resistance to inspiration and decreased resistance toexpiration. Such orientation may be used for a variety of pulmonary,cardiac, inflammatory, neurologic, or other disorders that might benefitfrom such changes in resistance and its subsequent changes tointra-thoracic and airway pressures. This version of the device may bestructurally identical to other embodiments described elsewhere in thisapplication. In some versions, the respiratory device is reversible, sothat it may be used in either orientation by the user (e.g., to increasethe resistance of inspiration relative to expiration in one orientation,or to increase the resistance of expiration relative to inspiration inanother orientation). In some versions, the respiratory device is shapedso that the direction of the airflow resistor is immediately evident.For example, the respiratory device may be of a different shape or sizeon one end, or may include a visual indication. In one version, therespiratory device may be shaped so that it fits securely into arespiratory orifice only in one orientation (e.g., so that the airflowresistor inhibits the expiration more than it inhibits inhalation). Forexample, a flange or other mechanical stop may be used to insure properorientation, while simultaneously preventing migration of the devicefurther into the respiratory orifice.

In many embodiments, the device provides some level of resistance toexpiration. It may be preferable to have little if any effect onresistance to inspiration, though in some cases, some degree ofinspiratory restriction may be beneficial. In some versions of thedevice, both inspiration and expiration may be inhibited by the airflowresistor.

The device may also be adapted for comfort. Any device placed either inor around the oral cavity or in or around the nose should not bepainful, and if possible not very noticeable by the patient. Thus, theholdfast may be shaped to conform to the attachment site in or aroundthe respiratory orifice. In some versions, the holdfast comprises aflexible or shapeable material (e.g., a foam or other soft shape-memorymaterial). In some versions, the entire respiratory device comprises asoft material.

Furthermore, the device may be adapted so that it is more or lessvisible to others. In some cases, the device may be configured to beplaced high enough within the nostrils to make it difficult for othersto see. Furthermore, the device may be of any color and/or pattern thathelp to camouflage it. In other versions, it may be useful to includecolors and patterns that stand out, including ones that are fluorescentor otherwise offer increased visibility during the night or othersetting where ambient light is reduced.

In some versions, the respiratory device may be “one size fits all”, sothat it may be used with any patient (or any patient of approximatelythe same size), despite differences in shapes and sizes of theirnose/nostrils, oral cavity, teeth and other relevant anatomic features.In one version, the devices may conform to a range of sizes, for example“small,” “medium,” and “large” (or any other appropriate range, such as,e.g., a numerical range). Alternatively, the devices may involve acustom fit of the device or devices to the patient.

Custom fitting may improve patient comfort and potentially improveperformance by improving the seal between the device and the patient'soral cavity, mouth, nasal cavity and nostrils, for example. In someversions, custom fitting may involve the placement of a device in warmor cold liquid or air with subsequent placement in the patient's nose ormouth. This process is meant to “prime” the materials in the device(e.g., particularly the materials of the holdfast), so that whenholdfast is secured to the patient, the device permanently assumes ashape or configuration corresponding to a portion of the patientsanatomy.

In some version of the devices described herein, an airflow resistor mayfit within a larger structure (such as the passageway) so that someairflow through or around the airflow resistor is always allowed. Forexample, there might be a constant opening between the airflow resistorand the anchor that secures the airflow filter in communication with thepassageway. This may ensure that expiratory and/or inspiratory airflowis never completely occluded. In some versions, the airflow resistorcomprises a “hole” or opening. For example, a flap valve may comprise anopening through the flap valve permitting airflow through the flap valveeven when the valve is closed.

The device may also create a PEEP effect by differentially changing theresistance to airflow in one direction based on the pressure appliedagainst the device. For example, in some designs, expiratory airflow issubjected to resistance by the airflow resistor (or valve) until acertain threshold pressure differential or level of airflow is achieved;below that threshold, a more complete closure of the airflow resistoroccurs (potentially completely occluding airflow through the device).The desired levels of PEEP are on the order of about 0.1 to about 30 cmH₂O and more preferably about 1 to about 15 cm H₂O pressure. Similarly,the differential resistance may also be triggered in the oppositedirection; for example, above a certain threshold of pressure or levelof airflow, the airflow resistor (e.g., valve) may open to decrease theresistance due to the airflow resistor, as when a patient coughs,sneezes, or blows his or her nose.

The optimal level of expiratory resistance or PEEP provided by thedevice may vary from patient to patient. In some versions, adequateexpiratory resistance or PEEP is created to offer the desired benefits,but not providing too much expiratory resistance or PEEP so that thepatient preferentially begins breathing through the mouth. In somecases, the user may test the device or devices while being monitored bya healthcare provider, a camera, a polysomnograph, or any other devicethat will help to assess the optimal level of resistance or therapyprovided by the subject devices.

The use of an airflow resistor may also alter the inspiratorytime:expiratory time ratio (I:E ratio), which is defined as the ratio ofinspiratory time to expiratory time. The desired I:E ratio will bebetween about 3:1 and about 1:10 and more preferably about 1:1.5 toabout 1:4 depending on the needs of the individual patient. In someversions, the desired ratio is approximately about 1:3.

In some versions, the device comprises an insertion, adjustment, orremoval mechanism. In some cases, this mechanism involves anyappropriate rigid or non-rigid positioner that facilitates removal orpositioning of the device. Non-rigid positioners include but are notlimited to cables, chains, wires, strings, chains, sutures, or the like.Rigid positioners include knobs, handles, projections, tabs, or thelike. A user may grasp or otherwise manipulate the positioner tofacilitate insertion, re-adjustment, or removal of the device.Furthermore, various applicators or other insertion devices may be used.For example, a tubular applicator holding a respiratory device adaptedfor insertion into a nasal cavity may be advanced into the nasalrespiratory orifice (e.g., nostril) to insert the respiratory device.

In some cases, the device may be oversized. Oversizing the device mayreduce resistance in one or more direction of airflow. In some versions,the passageway through the device is oversized. In some versions, anouter portion of the device that contacts the respiratory orifice isoversized. Thus, the respiratory device may exert pressure against thenasal cavity of a user. In patients with obstructive sleep apnea orsnoring, for example, increasing the size of the a respiratory deviceconfigured to be inserted into one or more nostrils may prevent the moredistal tissues of the airway, tongue, and nasopharynx from being suckedin or closed during inspiration. Moreover, airflow through an oversizedpassageway may assume a less turbulent flow profile, resulting in adecreased propensity for noise production in the case of snoring, forexample. Similarly, the respiratory device passageway may be shaped soas to decrease turbulence of airflow. Likewise, the shape and activityof the airflow resistor may be chosen to minimize turbulence and,therefore, sound or vibration.

In some versions, the device is used with an active agent. In someversions, the active agent comprises a drug. An active agent (e.g., amedicament) or other compound can be placed in or on the device todeliver the active agent into the mouth, tongue, hard and soft palates,sinuses, nose, pharynx, vocal cords, larynx, airways, lungs, trachea,bronchi, bronchioles, alveoli, air sacs, or any tissues that are exposedto inspiratory or expiratory airflow. In some cases, the active agentmay be embedded or impregnated in the device or components of thedevice. In some cases the active agent is a coating. An active agent maycomprise any compound that is in some way useful or desirable for thepatient. For example, the active agent may be any odorant, including:menthol, phenol, eucalyptus, or any agent that provides a fragrance inthe inspired air. Alternatively, an active agent may comprise a drugwith beneficial effects, such as beneficial vasculature effects. Forexample, an active agent may comprise a drug that effects the bloodvessels (oxymetazoline or any other vasoactive compound), nasopharynx,airways or lungs (albuterol, steroids, or other bronchoconstriction orbronchodilation compounds). An active agent may comprise an antibioticor a steroid for example. The above list of active agents is not meantto be limiting.

An active agent may be placed in or on any portion of the device.Furthermore, the location of the active agent within the respiratorydevice may specifically guide the delivery of the active agent. Forexample, in versions of the respiratory device configured to be placedinside a respiratory cavity, when the holdfast comprises an active agent(e.g., coated, embedded or otherwise part of the holdfast), the drug maybe delivered through the mucus membranes of the respiratory cavity. Inanother example, an active agent may be included as a powder orreleasable coating that may be aerosolized and delivered within therespiratory system. Thus, an active agent may be on a surface of thedevice (e.g., the passageway, holdfast or airflow resistor) or embeddedwithin any surface of the device. A separate drug-containing region mayalso be included in the device. The addition of an active agent may beof particular interest in treating allergies and sinusitis. Respiratorydevices (with or without airflow resistors) may therefore compriseactive agents such as menthol or other fragrant compounds.

In some versions of the devices, an airflow resistor is not present. Thedevice may comprise a passageway and a holdfast and may or may notinclude additional support such as a rim. In some cases, the holdfastmay be of adequate strength to support and prevent migration or movementof the device, and to provide adequate radial support to preventreduction of the passageway of the device during the various phases ofthe respiratory cycle. In this case, the device props open the nasal ororal cavities to facilitate inspiratory and/or expiratory airflow. Thismay be helpful in preventing obstructive sleep apnea and snoring sincethese disorders can be treated, for example, by increasing the size ofthe nares. This is partly due to the tendency of the nares and nasalcavity to collapse due to negative inspiratory pressures. Thus,preventing these nasal tissues from collapsing may prevent furtherdownstream tissues in the nasopharynx from collapsing. As mentionedearlier, the device may be oversized relative to the size of the naresor nasal cavity in order to reduce resistance and maximize airflow.

The respiratory devices may be manufactured and assembled using anyappropriate method. Representative manufacturing methods that may beemployed include machining, extruding, stamping, and the like.Assembling methods may include press-fitting, gluing, welding,heat-forming, and the like.

Turning now to the figures, FIG. 1 provides a perspective view of oneversion of the respiratory device 1 in which the device can fit into theoral cavity of a user. The holdfast 5 comprises grooves 2 and 3 in whichthe user's teeth and/or gums may preferentially sit, thus securing thedevice in the oral cavity. Airflow resistor 4 represents any airflowresistor capable of modulating inspiratory and/or expiratory resistanceduring any or all portions of the respiratory cycle, as described above.The airflow resistor 4 sits within a passageway 6.

FIG. 2 is a perspective view of another embodiment of the respiratorydevice 1 that may be fitted in an oral cavity. In this embodiment, thepatient's teeth and/or gums help to secure the device in place bycontacting the holdfast. The holdfast comprises an inner frame 10, andouter frame 12, and a positioner 14. The inner frame 10 is located onthe internal portions of the patient's teeth or gums. The outer frame 12is positioned outside the patient's teeth/gums or outside the patient'slips. The positioner 14 is located between the upper and lower jaws,teeth, and/or gums. An airflow resistor 4 modulates inspiratory and/orexpiratory resistance during any or all portions of the respiratorycycle.

FIG. 3 is a view of the device 1 shown in FIG. 2, where the device isdepicted within and protruding from the patient's oral cavity. The outerframe 12 of the holdfast is shown outside of the patient's teeth andgums. The airflow modulator 4 within the passageway 6 modulatesinspiratory and/or expiratory resistance during any or all portions ofthe respiratory cycle through the oral respiratory passageway. One ormore airflow resistors 4 and/or passageways 6 may be used in this (orany, e.g., oral or nasal) respiratory device.

FIG. 4 is a perspective view of another embodiment of the respiratorydevice 1 in which the device is removable and may be secured within apatient's nasal cavity 16. In this embodiment, the device protrudes fromthe nasal opening. The sides of the device comprise a holdfast which isshown fitting snugly within the nasal passage, as well as projecting outfrom the nasal passage.

FIG. 5 is a perspective view of another version of the respiratorydevice 1 in which the device is placed completely within the nasalpassage 16. The entire respiratory device fits snugly within the nasalpassage.

FIG. 6 is a cross-sectional view of a respiratory device 1 similar tothose shown in FIGS. 4 and 5. A holdfast 28 comprises the outer surfaceof the device that contacts the inner portions of the nasal cavity, thusserving to secure the device in place while ideally creating a partialor complete seal. The passageway 6 through which air may flow issurrounded by a rim 30 that provides additional structural support tothe device. A rim 30 is not required, particularly if the walls of thepassageway (which may be defined by the holdfast 28, for example)provide sufficient support. An airflow resistor 24 is included withinthe passageway which may modify inspiratory and/or expiratory resistanceduring any or all portions of the respiratory cycle.

FIGS. 7 a and 7 b show more detailed views of the operation of airflowresistors shown in FIGS. 4 and 5. These cross-sectional views illustratethe holdfast 28, the optional rim 30, the passageway 6, and the airflowresistor, shown as a valve 32. The rim 30 separates the holdfast 28 andthe valve 32, frames the valve 32, and provides overall structuralsupport to the entire device. In FIG. 7 a, the valve 32 is shown in theopen position, providing less resistance to airflow. In FIG. 7 b, valve32 is shown in the closed position, providing more resistance toairflow, because the cross-sectional area of the passageway 6 has beenconstricted by the closing of the valve.

FIGS. 8 a and 8 b show perspective views of an airflow resistor thatcould be used, for example with any of the devices described in FIGS.1-5. In these figures, a rim 30 is shown. The rim may be part of theholdfast which positions and secures the device within a respiratorypassageway; alternatively, additional material (e.g., compliantmaterial) may be attached to the rim to form the holdfast. In FIGS. 8 aand 8 b, the rim provides support to the airflow resistor 24. Theairflow resistor is shown here as a flap valve mechanism that comprisesa flap 36 that pivots around a joint 38 and is connected to a fixedelement 40. Fixed element 40 is attached to the inner region of thepassageway 6, which is defined in this figure by the rim 30. In someversions, the flap valve and the inner surface of the passageway 6(e.g., the rim 30) may constitute a single piece. Alternatively, theflap 36, joint 38, and fixed element 40 may be fabricated as a singlepiece, in which case joint 38 may be a hinge. Thus, joint 38 may be apinned hinge or a non-pinned hinge joint. Alternatively, rim 30, flap36, joint 38, and fixed element 40 may all be created as a single pieceor material. Thus, flap 36 is able to pivot in relation to fixed element40 depending on the direction of the patient's airflow and the desiredlevel of resistance to airflow. FIG. 8 a shows the airflow resistor withflap 36 in a closed position during expiration, thus providing increasedresistance. In some versions, the flap portion of the airflow resistorcloses completely, as shown. In these versions, the edges of the flap 36may close off the entire passageway (as shown), or may only occlude aportion of the passageway. FIG. 8 b shows the airflow resistor with flap36 in the open position (e.g., during inspiration), thus providingdecreased resistance. Flap 36 may define a hole, or may have otheropenings (which may stay open during all or part of the respiratorycycle) to help modulate the degree of inspiratory and expiratoryresistance. The flap 36 may return to a preferred opened or closedposition. For example, a shape memory material, a spring (such as atorsion spring), or the holdfast may apply force to flap 36 to return itto a closed position. For example, the use of foam or urethanesurrounding the airflow resistor may provide such force as to close flap36 in the absence of adequate airflow. Bi-leaflet versions of theairflow resistor are also contemplated and will have similar function.These bi-leaflet versions may involve multiple sets of flaps 36, joints38, and fixed elements 40, etc.

FIGS. 9 a and 9 b show a perspective view of another embodiment of anairflow resistor that could be used in any of the respiratory devicesdescribed herein. The inner surface of the passageway shown includes arim 30 that supports the airflow resistor. This airflow resistor 24 isalso shown as a valve mechanism. Moveable elements 42 a and/or 42 b(flaps) are attached to one another or are constructed from a singlepiece. Moveable elements 42 a and 42 b are attached to the inner surfaceof the passageway (shown as a rim 30) at attachment points 44 a and 44b, and these attachment points may allow the valve to pivot around ahinge 43 in response to direction and amplitude of airflow. In oneversion, attachment points 44 a and 44 b are formed directly into therim 30 or holdfast 28 during the manufacturing (e.g., casting) process.In one version, the hinge is statically attached to an inner region ofthe passageway, and the flaps 42 a and 42 b are movably (or flexibly)attached to the hinge. FIG. 9 a shows this airflow resistor when theresistance is high (e.g., the flap valve is mostly closed), as duringexpiration, and FIG. 9 b shows the airflow resistor when the resistanceis low (e.g., the flap valve is mostly open), as during inspiration.

FIG. 10 shows a perspective view of another embodiment of an airflowresistor that is similar in structure and function to the device shownin FIGS. 9 a and 9 b. However, the airflow resistor shown has aninternal opening 45 that is located approximately where moveableelements 42 a and 42 b pivot relative to one another. The addition ofinternal opening 45 modulates airflow (e.g., inspiratory or expiratoryairflow) by altering the level of resistance. Addition of this openingreduces the resistance in one direction (e.g., expiratory resistance,when the flap valve is “closed”) more than resistance in the oppositedirection (e.g., inspiratory resistance, when the flap valve is “open”).

FIG. 11 shows a perspective view of another embodiment of an airflowresistor that is similar in structure and function to the device shownin FIGS. 9 a and 9 b. Peripheral openings 46 a and 46 b are placedcompletely within, or on the periphery of the moveable elements 42 a and42 b. These peripheral openings 46 a and 46 b also modulate inspiratoryand/or expiratory resistance. The addition of peripheral openings 46 aand 46 b helps modulate inspiratory and expiratory airflow by alteringthe level of resistance. Addition of these peripheral openings alsoreduce the resistance in one direction (e.g., expiratory resistance,when the flap valve is “closed”) more than resistance in the oppositedirection (e.g., inspiratory resistance, when the flap valve is “open”).

FIGS. 12 a and 12 b show more detailed views of the operation of thevalve mechanisms as described in FIGS. 9 a, 9 b, 10, and 11. In thisfigure, we assume that the airflow resistor is oriented so that theairflow resistor increases resistance during expiration relative toinhalation (e.g., the lungs are located to the right in FIGS. 12 a, 12 band 12 c). Moveable elements 42 a and 42 b are coupled to each other viahinge 43. FIG. 12 a demonstrates the valve mechanism during expiration,in which moveable elements 42 a and 42 b are in a closed position due tothe expiratory airflow in the direction from the lungs to the externalenvironment. FIG. 12 b demonstrates the valve mechanism duringinspiration, in which moveable elements 42 a and 42 b are in an openposition due to the inspiratory airflow in the direction from theexternal environment to the lungs. FIG. 12 c demonstrates a modificationof the valve mechanism shown in FIGS. 12 a and 12 b in which there areone or more apertures within or on the periphery of the moveableelements that reduce resistance to expiratory airflow, furtherincreasing the rate of expiratory airflow. All of these valve mechanismsand configurations can be placed in the opposite orientation so thatinspiratory airflow leads to valve closure and expiration leads to valveopening.

Moveable elements (flaps) 42 a and 42 b of the airflow resistor may bemade of any appropriate material. In particular, materials which havesufficient stiffness to withstand the forces applied by the respiratoryprocess. Furthermore, durable materials (e.g., which may withstand themoisture, etc. of the respiratory passage) may also be desirable. Insome versions, the devices are disposable, and thus durability may beless critical. Furthermore, the moveable elements 42 a and 42 b may alsobe made from porous materials or filters, etc. that do not overlyrestrict or resist airflow but at the same time can remove debris,pollen, allergens, and infectious agents for example.

FIGS. 13 a and 13 b show perspective views of another airflow resistorthat could be used in any of the devices described herein. FIG. 13 ashows the airflow resistor (a flap valve) in a closed position, as mightbe seen during expiration, resulting in increased resistance to airflow.FIG. 13 b shows the airflow resistor in an open position, as might beseen during inspiration, resulting in a decreased resistance to airflowrelative to the closed position. Because of the small profile of theretracted flap valves, the resistance added by the airflow resistor whenthe airflow resistor is “open” may be negligible. Moveable elements 42 aand 42 b are attached to each other or are a single piece. Moveableelements 42 a and 42 b are attached to the walls of the passageway (inthis example, defined by a rim 30), to the rim 30, or to the holdfast 28by a securing element 54 a and 54 b which uses a tab, adhesives, pressfit, external pressure (as from a holdfast 28) or any way known to thoseskilled in the art. Internal opening 45 is located centrally, decreasingthe resistance to expiratory airflow (in the “closed” state), althoughperipheral locations are also contemplated. In some versions, the sizeand number of openings in the valves may determine the resistance of theairflow resistor. Thus, the size and number of openings may be selectedin order to determine the I:E ratio.

FIG. 14 provides a perspective view of another embodiment of an airflowresistor that is similar in structure and function to the airflowresistor shown in FIGS. 13 a and b. In FIG. 14, the movable elementsfurther comprise a reinforcement support 60 a and 60 b that is locatedpartially or completely covering the moveable elements 42 a and 42 b.The reinforcement support provides additional structure and/or supportto these moveable elements. Furthermore, reinforcement support 60 a and60 b may also promote a more reliable seal and may standardize themovements of moveable elements 42 a and 42 b while reducing thelikelihood that moveable elements will invert, buckle in the directionof airflow, or otherwise fail, especially when exposed to high pressuresand airflow as might be seen during coughing. The addition ofreinforcement support 60 a and 60 b also dampens any whistling or othersounds during inspiration or expiration. Moveable element 42 a andreinforcement support 60 a and moveable element 42 b and reinforcementsupport 60 b may be a single unit (or each “flap” may be a single unit).Alternatively, both moveable elements 42 a and 42 b and bothreinforcement support 60 a and 60 b may be a single unit. A centralopening 45 is also shown in the figure.

FIGS. 15 a-15 c show perspective views of another embodiment of anairflow resistor that may be used in any of the devices describedherein. The airflow resistor is similar to that shown in FIGS. 13 a and13 b with the exception that internal opening 45 is replaced by anotherairflow resistor 64 (a “nested airflow resistor”). This nested airflowresistor 64 automatically closes when the flow through the valve (or thepressure differential across the valve) falls below a predeterminedlevel. This allows the airflow resistor (with the nested airflowresistor region) to provide positive end expiratory pressure (PEEP). InFIG. 15 a, the airflow resistor is shown during exhalation, and themoveable elements 42 a and 42 b of the airflow resistor are in theclosed position. The nested portion of the airflow resistor 64 is openso long as the pressure differential across the airflow resistor and/orairflow is above a certain level. Thus, this figure demonstrates thebeginning of expiration, when airflow in the passageway and pressuredifferential are largest. In FIG. 15 b, the same airflow resistor isagain shown during expiration, and moveable elements 42 a and 42 b ofthe airflow resistor are still in the closed position. However, thenested airflow resistor region 64 now assumes a closed position, sincethe pressure differential across the airflow resistor and airflowthrough the passageway is no longer above the threshold value. Thisscenario may correspond to the later stages of exhalation, when airflowand pressure differential are decreasing or are lower. Thus, at the endof exhalation, PEEP has been created. For example, the nested airflowresistor 64 may be set to close whenever air pressure in the respiratoryorifice coming from the lungs is less than 5.0 cm H₂O. FIG. 15 c showsthe device during inhalation, in which moveable elements 42 a and 42 bof the airflow resistor are in the open positions, allowing inhalatoryairflow with minimal resistance to said airflow.

FIGS. 16 a and 16 b show perspective views of another embodiment of anairflow resistor that may be used in any of the devices describedherein. FIG. 16 a shows a hingeless valve 76 in a closed position duringexhalation, in which there is increased resistance to airflow. FIG. 16 bshows a hingeless valve 76 in an open position during inspiration, inwhich there is decreased resistance to airflow. The hingeless valve 76may also comprise one or more holes within its structure to allowairflow in either direction at various stages of the respiratory cycle.For example, despite being in a closed position, the hingeless valve 76would still allow some level of expiratory airflow. Alternatively, thehingeless valve 76 might never close completely. Even in a closed state,its flaps may never completely block all airflow.

FIGS. 17 a and 17 b show perspective views of another embodiment of anairflow resistor that could be used in any of the devices describedherein. The membrane-type airflow resistor show in FIGS. 17 a and 17 bcomprises a membrane 80 (that may or may not be floppy) that is attachedby a connector 82 to the body of the airflow resistor. Duringexhalation, shown in FIG. 17 a, the membrane 80 seats itself against arim 30 and/or an apposition support 84 which may project from the sidesof the passageway (e.g., from the rim 30) to support the membrane 80during exhalation. FIG. 17 b shows the situation during inhalation, whenthe membrane 80 in a deflected position, thereby decreasing resistanceto inspiratory airflow, and increasing airflow through the airflowresistor. Membrane 80 may have an opening 86 (or openings) which remainopen during both inspiration and exhalation. In some versions of theairflow resistor, membrane 80 does not have an opening. In still otherversions, there are several openings within membrane 80.

FIGS. 18 a and 18 b show cross-sectional views of another embodiment ofan airflow resistor that could be used in any of the devices describedherein. FIG. 18 a shows the airflow resistor during inspiration, duringwhich deformable member 90 is unfurled leading to decreased resistanceand increased airflow. FIG. 18 b shows the airflow resistor duringexpiration, during which deformable member 90 assumes an orientation orfolding configuration that leads to increased resistance and decreasedairflow. Deformable member 90 may have a preferred default position (atendency to default to a preferred orientation in the absence ofexternal influences or pressures) that may allow such an airflowresistor to offer a PEEP effect.

FIGS. 19 a and 19 b show cross-sectional views of another embodiment ofan airflow resistor that could be used in any of the devices describedherein. This is a stopper-type airflow resistor. FIG. 19 a shows theairflow resistor on exhalation with little to no airflow and minimalpressure differential across the valve. FIG. 19 b shows the deviceduring more robust exhalation, characterized by increased airflow andincreased pressure differential across the valve. Stopper 92 isconnected to return mechanism 94. Stopper 92 may also have an openingwithin it to allow airflow at all times or at specific parts of therespiratory cycle (e.g., another, nested, airflow resistor, such as oneallowing airflow during inhalation, but not exhalation), therebyproviding fluid communication between the airways and the externalenvironment. Alternatively, stopper 92 may have a valve portion that isopen during inhalation and closed during exhalation, or vice verse. InFIG. 19 a, the airflow from right to left is insufficient to overcomethe spring force provided by return mechanism 94, and stopper 92 sealsagainst seating supports 96 a and 96 b. In FIG. 19 b, the airflow fromright to left is sufficient to overcome the spring force provided byreturn mechanism 94, and stopper 92 is displaced leftward and thusexpiratory airflow is allowed. The mechanism described in FIGS. 19 a and19 b is one way in which PEEP can be created by the device.

FIG. 20 is a perspective view of another embodiment of the respiratorydevice where the device is removable and may be placed in communicationwith the nasal cavity. In FIG. 20, a holdfast 28 is located between thepatient's nose and the airflow resistor in the device 1, providing apartial or complete seal, anchoring the device, and providing comfortfor the patient. The holdfast 28 has a cross section that is roughlycircular and capable of fitting within a patient's nostrils.

FIG. 21 is a perspective view of another embodiment of a respiratorydevice where the device is removable and may be placed within the nasalopening. This device shows a holdfast 28 having an approximately ovalcross-section. Many such cross-sectional shapes are possible to optimizeplacement, anchoring, sealing, and comfort, including a variety ofconical or asymmetric shapes designed to fit within a patient's nasalopenings. In some cases, the rim 30 and/or any airflow resistor 4 mayalso assume any desired cross sectional shape, including that of an ovalor any other non-circular orientation. In some embodiments, the holdfast28 will be shapeable, deformable, or adjustable by the patient eitherbefore, after, or during placement of the device. Alternatively, thedevice can be customizable to fit individual patients through the use ofimaging modalities including MRI, CT, xray, or direct vision, or throughthe use of molding techniques that are common in dentistry and otherfields.

FIG. 22 is a cross-sectional view of an embodiment of a respiratorydevice where the device is removable and may be secured in fluidcommunication with a nasal cavity. In this version, the device does notcontain any moveable components that alter airflow. The device comprisesa holdfast 28 and rim 30 that lends the device support. The device maybe oversized to decrease resistance and increase airflow in one or moredirections. In some cases, a drug (with either an active or inactiveingredient) may be embedded in or located on any of the device'scomponents, for example, the rim 30. It is appreciated that in somecases, there may be no rim 30, so long as structural support is providedby another component of the device, e.g., the holdfast. In this case,the drug may be loaded or coated on the holdfast or within thepassageway.

FIG. 23 shows a cross-sectional view of another embodiment of arespiratory device where the device is removable and may be secured incommunication with a nasal cavity. In this figure, there are two airflowpassageways. Each passageway is shown with an airflow resistor 24therein. The holdfast 28 surrounds both passageways, and each passagewayincludes an (optional) rim 30. Each of the flow resistors 24 mayincrease or decrease resistance to airflow independently and may worksimultaneously or at different times during the respiratory cycle. Forexample, in some cases, during inhalation, one of the airflow resistors24 may decrease resistance to airflow while the second airflow resistor24 increases resistance to airflow. On exhalation, the first airflowresistor 24 may increase resistance to airflow while the second airflowresistor 24 decreases resistance to airflow. In other words, inspiratoryairflow may proceed through one location, and expiratory airflow mayproceed through a second location within the same device.

FIG. 24 is a cross-sectional view of another embodiment of therespiratory device where the device is removable and may be secured incommunication with a nasal cavity. The device is shown with a fixedfilter 98 that is located in the path of the airflow as it traverses thedevice. The fixed filter 98 may help clear the airflow of any solid orliquid particles, debris, odors, allergens, pollen, and/or infectiousagents. This filter 98 may remain roughly fixed in place during allparts of the respiratory cycle though some degree of movement may bepermitted. A drug may be placed within or on the surface of one or morecomponents of the device to provide additional benefit to the patient.The addition of fixed filter 98 may not lead to increased resistance ineither direction, unless such a design is desired. The fixed filter 98can be created from any number of filter materials that are known tothose skilled in the art. This fixed filter 98 may be used in any of therespiratory devices herein, in addition to, or as an alternative to, anairflow resistor 4.

FIG. 25 is a cross-sectional view of another embodiment of therespiratory device, where the device is removable and may be secured incommunication with a nasal cavity. The respiratory device of FIG. 25comprises a moveable cleansing filter 100 that is shown located withinthe device, and which may help to clear the airflow of solid or liquidparticles, debris, odors, allergens, pollen, and/or infectious agents.In some versions, the filter may be configured to move so that itfilters only during inhalation (or exhalation), or may move out of theway during periods of extremely large airflow (or air pressure) in theairflow passageway (e.g., during coughing, nose blowing, sneezing).

FIGS. 26 a and 26 b are perspective views of one version of a moveablecleansing filter where the moveable cleansing filter is shown duringinhalation and exhalation respectively. A movable cleansing filter maybe a movable filter, scrubber, or any other device capable of removing(particularly selectively removing) any solid or liquid particles,debris, odors, allergens, pollen, and/or infectious agents. Thismoveable cleansing filter may be used in any of the respiratory devicesherein, in addition to, or as an alternative to, an airflow resistor 4.FIG. 26 a shows the moveable cleansing filter (shown as movable filters)during inspiration (during which airflow travels from right to left inthe figure) leading to displacement of moveable filter elements 102 aand 102 b away from one another. FIG. 26 b shows the moveable cleansingfilter during expiration (during which airflow travels from left toright in the figure) leading to displacement of moveable filter elements102 a and 102 b towards one another. Thus, on inspiration, airflowpasses through the moveable filter elements 102 a and 102 b and the airmay be cleansed of the relevant substances. On expiration, airflowpasses both through and around moveable filter elements 102 a and 102 b.The addition of moveable filter elements 102 a and 102 b ideally doesnot lead to increased resistance in either direction, unless such adesign is desired. The moveable filter elements 102 a and 102 b can becreated from any number of filter materials that are known to thoseskilled in the art. One or more openings or apertures may be placedwithin the moveable filter elements 102 a and 102 b to alter inspiratoryor expiratory resistances.

FIG. 27 is a three dimensional view of another embodiment of the subjectdevices where the device is removable and secured in communication withboth nasal cavities. Nasal mask 108 is positioned securely against thenose and face in order to minimize or eliminate the possibility of airleak around the periphery of the device. The device includes a holdfastcomprising straps 110 a and 110 b (that facilitate the securepositioning) and a nasal mask 108 that is secured against the face bythe straps. The mask's airflow resistor 116 modulates inspiratory and/orexpiratory resistance during any or all portions of the respiratorycycle. There is at least one airflow resistor 116 located on the device,though two or more airflow resistors 116 may be used (e.g., one placedin proximity to each nostril).

FIG. 28 is a cross-sectional view of another embodiment of therespiratory device, where the device is removable and may be secured incommunication with a nasal cavity. In FIG. 28, a respiratory devicefurther comprises a respiratory gas supply. A respiratory gas inlet 120is shown attached to the respiratory device, providing gas, such as pureoxygen or mixed oxygen to the passageway. An airflow resistor 24 isincluded within the passageway which may modify inspiratory and/orexpiratory resistance during any or all portions of the respiratorycycle. In some versions of the device, the airflow resistor 24 duringexhalation may feature a flap mechanism in which the flap partially orcompletely occludes respiratory gas inlet 120, thereby only providingrelease of gas when the patient is inhaling and the flow resistor 24 istherefore open to some degree. The device that provides the respiratorygas may be permanently or non-permanently fixed, attached, or otherwisecoupled to the holdfast, rim, or airflow resistor via a press fit,adhesive, or in some other fashion. In some cases, the respiratory gassupply may be an off-the-shelf device that that provides respiratorygas, as is currently available from multiple manufacturers.

The aforementioned devices and methods of using them may provide a firstairflow resistance to airflow from proximal airways to distal airways(inhalation) and a second flow resistance to airflow from distal airwaysto proximal airways (expiration). In some of the respiratory devicesdescribed herein, when expiratory airflow and/or expiratory airwaypressures fall below a threshold (one that is too low to keep an airflowresistor mechanism open), expiration airflow will be stopped, leading toPEEP. As a result, normal inspiration, normal expiration, and PEEP areaccommodated while offering potential benefits to the patient, includingclinical benefits.

Uses of the Respiratory Devices

The respiratory devices and methods described herein may be used for avariety of therapeutic and non-therapeutic purposes. A description ofsome of these uses is given below. The respiratory devices and methodsdescribed herein may be used in other ways as well, and these examplesare not to be considered exhaustive.

Generally, the respiratory devices described herein may improve therespiratory and cardiovascular function of a person in need thereof(e.g., a patient). Thus, these respiratory devices may be usedtherapeutically, for example, to cure, treat or ameliorate the symptomsof a variety of medical disease states. Furthermore, the respiratorydevices may be useful in generally improving the health and well beingof any person.

Disease states which may be treated by the devices and methods describedherein include but are not limited to: heart failure (right-sided and/orleft-sided), COPD, pulmonary edema, sleep apnea (obstructive and/orcentral), sleep-disordered breathing, Cheyne-Stokes respiration,insomnia, snoring and other sleep disorders, asthma, bronchomalacia,acute lung injury, ARDS, cystic fibrosis, hypoxemic respiratory failure,gastroesophageal reflux disease, hiatal hernia, heartburn, hypertension,myocardial infarction, arrhythmia, cardiomyopathy, cardiac valve disease(either stenosis or regurgitation of the mitral, aortic, tricuspid, orpulmonic valves), stroke, transient ischemic attack, increased cerebralpressure, a variety of inflammatory diseases, and degenerativeneurologic conditions. Moreover, the devices be beneficial for patientsbeing weaned off mechanical ventilation, as well as post-operativepatients.

The increased pressure within the airways may reduce the amount andfrequency of pulmonary edema, a common consequence of heart failure.Afterload and preload on the heart may also be affected; for example,afterload and preload may be decreased in patients with heart failure.Filling pressures may be increased or, more likely, decreased.Decreasing filling pressure may potentially benefit patients withfailing hearts. Gas exchange may improve in many cases, leading toincreases in pO₂ and decreases in pCO₂. In some cases, the level of pCO₂may actually increase or become more stable and less likely tofluctuate. This increase in the stability of pCO₂ levels may lead toprofound benefits in patients with central sleep apnea and in patientswith Cheyne-Stokes breathing, for example.

Any location within the body that is exposed to respiratory airflow(including but not limited to the upper airway, trachea, bronchi,nasopharynx, oropharynx, nasal cavity, oral cavity, vocal cords, larynx,tonsils and related structures, back of the tongue, sinuses, andturbinates) may benefit from the increased airway pressure and increasedduration of expiratory airflow. In some cases, there will be a reductionin swelling andedema in these locations, leading to increased diametersof the airways and conduits in which the airflow passes. This leads toless of a tendency for these structures to collapse upon inhalation.Moreover, these structures may be less prone to create noise oninspiration or expiration, thereby reducing the quantity and/or qualityof snoring. Put another way, the reduction of edema in the airways maymake it less likely that these structures will collapse and may reducethe volume and frequency of snoring, apnea, or hypopnea. Furthermore,reduction in swelling and edema and improved lymphatic flow due to thesepositive pressures may reduce nasal congestion, inflammation, andsinusitis for example.

The respiratory device may also increase lung compliance. For example,lung compliance may increase partly if fluid which might otherwise be inthe lung and alveoli is driven away by the increased airway pressure.This increased lung compliance may make it easier to breathe and mayrequire less effort and force on the part of the patient to displace thediaphragm a certain distance to achieve a certain tidal volume.Moreover, increased lung compliance may decrease the pressuredifferential between the alveoli and mouth. As this pressuredifferential decreases, it becomes less likely that an inhalationattempt will induce a collapse of the upper airway. Thus, an increase inlung compliance may herald a reduction in the frequency or severity ofobstructive sleep apnea or hypopnea episodes. Similarly, snoringfrequency and severity (volume) may be reduced for similar reasons.

The respiratory device may also improve ejection fraction. This effectmay be mediated via increases in intra-thoracic pressure and alterationsin transmural pressures and the beneficial effects on preload andafterload on the failing heart. In addition to left-sided benefits tothe heart, there may also be benefits afforded to the right side of theheart. Improving ejection fraction with the respiratory devicesdescribed herein may result in positive short- and long-term changes tothe energetics and biologic properties of the heart tissue. Some ofthese positive changes may mimic the positive remodeling changes seen inhearts treated with various complicated cardiac support devices such asthose developed by Acorn Cardiovascular (St. Paul, Minn.) and ParacorMedical (Sunnyvale, Calif.). These expiratory resistors use thepatient's own intra-thoracic pressure to “support” the patient's heart.Moreover, because the support potentially provided by the respiratorydevices described herein is not limited to just the ventricle, it maysupport the atria, which can also be severely affected by heart failureand other cardiac or pulmonary diseases. There may be reductions in leftventricular and left atrial sizes, both in the shorter and longer term.Furthermore, cardiac sympathetic activation may be reduced, and cardiacoutput may be increased or decreased depending on the nature of theresistance provided.

There are a variety of other beneficial effects of enhanced expiratoryresistance and increases in intra-thoracic pressure that may be achievedwith the respiratory devices described herein. Examples includedecreased heart rate and blood pressure. There may be a reduction in thenumber of arrhythmias, including but not limited toatrial/supraventricular and ventricular fibrillation,atrial/supraventricular and ventricular tachycardias, heart block, andother common arrhythmias. Thus, the respiratory devices described hereinmay also reduce the incidence of sudden cardiac death and other cardiacdisorders. Furthermore, coronary perfusion may be expected to increase.Further, expiratory resistance and increased intra-thoracic pressuresmay lead to improvements in gastroesophageal reflux disease (ieheartburn), gastritis, Barrett's esophagus, esophageal cancer, hiatalhernia, and other causes of diaphragmatic hernia. This effect may bemediated by the compression of the esophagus located within the thoraxdue to the increased intra-thoracic pressures. As a result, food andother stomach contents may no longer be able to reflux superiorly intothe esophagus, which is otherwise common when patients are lying down.Furthermore, hernias (primarily hiatal) may be reduced and pushed backinto the abdomen by the increased intra-thoracic pressure. The use ofthese respiratory devices may have beneficial effects on othergastroenterologic conditions beyond those already described.

Cardiac valve disease, including but not limited to mitral, tricuspid,pulmonic and aortic regurgitation, and mitral, tricuspid, pulmonic andaortic stenosis may also benefit from the respiratory devices describedherein. In particular, the respiratory device may effect mitralregurgitation and may help prevent further annular dilatation (abyproduct of heart failure and generalized heart dilation).

Use of the respiratory devices described herein will result in areduction in respiratory rate, which may be very helpful in diseasessuch as COPD, asthma, hyperventilation, and anxiety disorders includingpanic attacks, among others. The ratio of inspiratory time to expiratorytime (I:E ratio) may be decreased with the device. Tidal volumes mayincrease as well. For example, in COPD, the increased resistance mayfacilitate improved expiratory function. This may also allow the patientto benefit from larger tidal volumes and increased minute ventilation.In embodiments in which the respiratory device creates PEEP (positiveend expiratory pressure), the amount of PEEP (or resistance generated bythe device) may overcome some, or all, of the intrinsic PEEP that iscommon in patients with COPD. In patients with COPD or other pulmonarydisorders, gas exchange may improve. In this case, gas exchange refersto the removal of CO₂ from the body and addition of O₂ into the bloodstream from inspired air. Thus, pO₂ may increase and pCO₂ may decrease,particularly in patients with COPD, but more generally in all patientstreated with the device. Moreover, oxygen saturation may increase,reflecting an increase of oxygen binding to hemoglobin.

Other benefits offered by the respiratory device may include a reductionin diaphragm fatigue and improved efficiency of the accessory muscles ofinspiration. This may make breathing significantly easier in patientswith pulmonary disease, and more specifically COPD and cystic fibrosis.

As previously mentioned, the respiratory devices described herein maydecrease respiratory rate. It has been shown that slowed breathingtechniques can lead to a reduction in blood pressure. Thus, the devicemay reduce blood pressure in a patient, including patients withhypertension (systemic and pulmonary). The reduction in blood pressuremay be systolic and/or diastolic. Reductions in blood pressure may be onthe order of 1-70 mm Hg systolic or diastolic. This may bring thepatient to normal (<140/80 mm Hg) or near normal (<160/100 mm Hg)levels. In patients who are being treated for hypertension, the devicecould be used as an adjunctive therapy to drugs or as a stand-alonetherapy in some patients. In some versions, a respiratory device asdescribed herein may be used for short periods (minutes, hours, orlonger) over a span of days to weeks to months to offer longer termbenefits for weeks or months after the cessation of therapy. Treatmentsmay last 15 seconds to 24 hours and may be repeated over a regular orirregular interval, for example, on the order of hours to days. Thedevices may be worn at night or day, while awake or during sleep, toslow respiratory rate. A reduction in blood pressure and/or heart ratemay be seen while the device is in place, or after the device has beenremoved. This may be due to hormonal influences whose effects lastlonger than the period in which the device is in place. Morespecifically, the device may work though either a sympathetic orparasympathetic pathway.

Expiratory resistance may also prolong expiratory time, which may reducethe respiratory rate. Thus, the devices described herein may be used toreduce respiratory rate. This may have benefits in treating insomnia,since it may promote a sense of relaxation in the user, throughincreased parasympathetic stimulation, decreased sympathetic simulation,and/other hormonal and non-hormonal effects. This may also promote asense of well being or relaxation that may allow the user to fall asleepeasier and quicker and improve sleep quality and quantity. Thus, therespiratory devices described herein represent a novel non-pharmacologicmethod of treating insomnia and promoting relaxation. The device may beused throughout the day and/or night to promote said relaxation and wellbeing.

The respiratory devices described herein may also be used to treat orameliorate disorders characterized by ineffective, non-productive, orotherwise disturbed inspiration (including but not limited toobstructive sleep apnea or restrictive pulmonary disease). For example,with the device in place, a patient may be more likely to have slightlyelevated lung volumes after exhalation. Put another way, more air thannormal may be present in the lungs after exhalation when using someversions of the device. Fewer alveoli may be collapsed; thus inhalationmay be easier because it will require less effort to re-open the alveoliduring the subsequent breath. Moreover, pulmonary congestion andpulmonary edema may also be reduced, so compliance may be improved. As aresult, it may require less effort for patients to inhale. It followsthat a smaller pressure differential (between the alveoli and the mouth)will be required. The smaller the pressure differential, the less likelythat the patient's conducting airways (including the upper airways andpharyngeal tissues) will collapse, thus reducing the likelihood ofobstructive sleep apnea, hypopnea, and snoring.

Infectious diseases may also benefit from the respiratory devicesdescribed herein. These diseases include but are not limited topneumonia (community and hospital acquired), tuberculosis, bronchitis,HIV, and SARS.

The respiratory devices may also be useful in pulmonary or cardiacrehabilitation. For example, the device may find use in patients withchronic pulmonary disease including but not limited to chronicbronchitis, emphysema, asthma, pulmonary fibrosis, cystic fibrosis, andpulmonary hypertension. Alternatively, the devices may benefit patientswith cardiac disease, including but not limited to: angina, myocardialinfarction, right or left sided heart failure, cardiomyopathy,hypertension, valve disease, pulmonary embolus, and arrhythmia.

Patients with obesity may also benefit from the use of the respiratorydevices described herein. Obesity can contribute to exercise intolerancepartly because it increases the metabolic requirement during activityand alters ventilatory mechanics by reducing functional residualcapacity (FRC) and promoting atelectasis. Obesity may also reducecardiac reserve, since a higher than normal cardiac output response isrequired during physical activity. This in turn may cause systemichypertension, which increases left ventricular afterload. Thus, thedevice, through its potential reduction in atelectasis and beneficialeffects on FRC, cardiac output, and blood pressure may be useful inpatients with obesity.

The respiratory devices may also be used by athletes, for example,during both aerobic and non-aerobic activities, partially because of thepotentially beneficial direct effects on the heart and on gas exchange.In some versions, the respiratory device may be oversized, to increasethe amount of inspiratory airflow, potentially increasing the amount ofoxygen transmitted to the lungs for gas exchange.

The respiratory devices described herein may also be used fortherapeutic and non-therapeutic effects on sleep. Sleep quality may beimproved, with more slow-wave sleep, fewer arousals, and improved REMsleep. The user may have more productive sleep and may be less tiredduring the day. Furthermore, the beneficial effects of the device mayextend beyond the period of use, and into the daytime as well, even whenthe device's use is limited to the night (e.g., when the user issleeping). In some cases, sympathetic discharge may be reduced and/orparasympathetic discharge may be increased. Thus, the device may havepositive benefits on the autonomic nervous system. This may offerbeneficial systemic effects as well as local effects, some of which havealready been described.

The respiratory devices described herein may also be used in otherlocations besides the nasal and oral cavities. Indeed, any location inthe body that is serves as an entry or exit location for respiratoryairflow or serves as a conducting airway or conduit for airflow maybenefit from the use of the devices described herein. For example, adevice may be used within, on the external surface of, or near a stomasite (e.g., for use in a patient after a tracheostromy).

Inflammation (which is present in a variety of disease states) may alsobe reduced using the respiratory device, possibly via the aforementionedparasympathetic or sympathetic mediated effects and/or effects of thevagus nerve and its stimulation. The treatment of any condition mediatedby an inflammatory cytokine cascade is within the scope of the devicesand methods described herein. In some embodiments, the respiratorydevice is used to treat a condition where the inflammatory cytokinecascade is affected through release of pro-inflammatory cytokines from amacrophage. The condition may be one where the inflammatory cytokinecascade causes a systemic reaction, such as with septic shock.Alternatively, the condition may be mediated by a localized inflammatorycytokine cascade, as in rheumatoid arthritis. Examples of conditionswhich may be usefully treated using the respiratory devices describedherein include, but are not limited to: appendicitis, peptic, gastric orduodenal ulcers, peritonitis, pancreatitis, ulcerative,pseudomembranous, acute or ischemic colitis, diverticulitis, epiglottis,achalasia, cholangitis, cholecystitis, hepatitis, Crohn's disease,enteritis, Whipple's disease, asthma, allergy, anaphylactic shock,immune complex disease, organ ischemia, reperfusion injury, organnecrosis, hay fever, sepsis, septicemia, endotoxic shock, cachexia,hyperpyrexia, eosinophilic granuloma, granulomatosis, sarcoidosis,septic abortion, epididymitis, vaginitis, prostatitis, urethritis,bronchitis, emphysema, rhinitis, cystic fibrosis, pneumonitis,pneumoultramicroscopicsilicovolcanoconiosis, alvealitis, bronchiolitis,pharyngitis, pleurisy, sinusitis, influenza, respiratory syncytialvirus, herpes, disseminated bacteremia, Dengue fever, candidiasis,malaria, filariasis, amebiasis, hydatid cysts, burns, dermatitis,dermatomyositis, sunburn, urticaria, warts, wheals, vasulitis, angiitis,endocarditis, arteritis, atherosclerosis, thrombophlebitis,pericarditis, myocarditis, myocardial ischemia, periarteritis nodosa,rheumatic fever, Alzheimer's disease, coeliac disease, congestive heartfailure, adult respiratory distress syndrome, meningitis, encephalitis,multiple sclerosis, cerebral infarction, cerebral embolism,Guillame-Barre syndrome, neuritis, neuralgia, spinal cord injury,paralysis, uveitis, arthritides, arthralgias, osteomyelitis, fasciitis,Paget's disease, gout, periodontal disease, rheumatoid arthritis,synovitis, myasthenia gravis, thyroiditis, systemic lupus erythematosus,Goodpasture's syndrome, Behcets's syndrome, allograft rejection,graft-versus-host disease, diabetes, ankylosing spondylitis, Berger'sdisease, Retier's syndrome, or Hodgkins disease.

Furthermore, the respiratory devices and methods of using them may beused by or applied to a variety of different types of animals.Representative animals with which the methods and devices find useinclude, but are not limited to: canines; felines; equines; bovines;ovines; etc. and primates, particularly humans. The respiratory devicesdescribed herein may also be packaged for use. For example, therespiratory devices may be packaged individually or as a set (e.g., insets of pairs, particularly in variations in which an individual deviceis used with each nostril). Furthermore, the packaging may be sterile,sterilizable, or clean.

The respiratory devices described herein may also be provided as part ofa kit that includes at least one of the devices. FIG. 29 shows anexample of a kit 2905 that includes a respiratory device (2901illustrating a packaged respiratory device) and instructions for how touse the device 2903. The instructions 2903 are generally recorded on asuitable recording medium. For example, the instructions may be printedon a substrate, such as paper or plastic, etc. As such, the instructionsmay be present in the kits as a package insert, in the labeling of thecontainer of the kit or components thereof (i.e., associated with thepackaging 2901 or sub-packaging) etc. In other embodiments, theinstructions are present as an electronic storage data file present on asuitable computer readable storage medium, e.g., CD-ROM, diskette, etc.The instructions may take any form, including complete instructions onhow to use the device, or references, directing a user to usingadditional sources for instructions (e.g., a website address with whichinstructions posted on the world wide web).

EXAMPLES

The following examples are offered by way of illustration and not by wayof limitation.

A. Removable Application in the Oral Cavity

A respiratory device adapted for use in the oral cavity (e.g., any ofthe devices shown in FIGS. 1-3) may be placed into a subject's mouth bymedical personnel or by the subject. The respiratory device may besecured in place by the subject's teeth, gums, tongue, lips, palate orshape of the oral cavity or surrounding anatomy including the jaw, nose,chin, or skin. The respiratory device may also (or alternatively) besecured by use of an adhesive, a securing strap, or by other holdfast.The use of an adhesive may further improve the seal between the deviceand the oral cavity. The device may be worn during the night or day,while the patient is awake or sleeping. In some cases, the device may beworn continuously for extended periods of time (e.g., minutes, hours,days). These devices are meant to provide benefits to subjects sufferingfrom COPD, heart failure, sleep apnea, insomnia, hypertension,gastroesophageal reflux disease, hiatal hernia and other medicalconditions mentioned previously.

In some embodiments, the device works as follows. During inhalation, thevalve mechanism remains in the open position as airflow proceeds fromthe external environment into the airways and lungs. Open position meansany position in which resistance to airflow is reduced or minimizedduring inhalation more than exhalation. This can be achieved using anyof the airflow resistor embodiments described earlier. Duringexhalation, the airflow from the airways and lungs to the outsideenvironment occurs, and an airflow resistor (e.g., a valve mechanism)subjects this exhalation airflow to greater resistance than duringinhalation. Thus, resistance during inhalation is less than exhalationresistance, providing the desired effect to the subject.

B. Removable Application in the Nasal Cavity

A respiratory device adapted for use in the nasal cavity (e.g., any ofthe devices shown in FIGS. 4, 5, 20, and 21) may be placed into one ormore of the subject's nostrils by medical personnel or by the subjecthimself. The respiratory device may be secured in place in the subject'snostrils by the interaction between the nostril cavity and the holdfastof the device, as shown in FIGS. 4 and 5. The use of an adhesive mayfurther improve the seal between the device and the nasal cavity. Thedevice may be worn during the night or day, while the patient is awakeor sleeping. In some cases, the device may be worn around the clock.These devices may provide benefits to subjects suffering from COPD,heart failure, sleep apnea, insomnia, hypertension, gastroesophagealreflux disease, hiatal hernia and other medical conditions, as mentionedpreviously.

In some embodiments, the respiratory device worn in a nasal cavity worksas follows. During inhalation, the valve mechanism remains in the openposition as airflow proceeds from the external environment into theairways and lungs. Open position means any position in which resistanceto airflow is reduced or minimized during inhalation more thanexhalation. This may be achieved using any of the airflow resistorembodiments described earlier. During exhalation, the airflow from theairways and lungs to the outside environment occurs, and valve mechanismsubjects this exhalation airflow to greater resistance than duringinhalation. Thus, resistance during inhalation is less than exhalationresistance, providing the desired effect to the subject. In someversions, it may be preferable to regulate the airflow of both nostrils.For example, it may be desirable to have a single respiratory devicethat regulates airflow into the nasal cavity (as in FIG. 27), or to havea respiratory device that has airflow resistors for both nostrils, or tosimply block all airflow through one nostril and use a respiratorydevice to regulate airflow through the other nostril.

C. Removable Filtering Application in the Nasal Cavity:

In one embodiment of the methods for using a respiratory device, arespiratory device as shown in either FIG. 24 or FIG. 25 is placed intoone of more of the subject's nostrils by medical personnel or by thesubject. The respiratory device is secured in the subject's nostrils(e.g., by the interaction between the holdfast of the device and thesubject's nostrils). The use of an adhesive may further improve the sealbetween the device and the nasal cavity. The device can be worn duringthe night or day, while the patient is awake or sleeping. In some cases,the device can be worn continuously. These devices may provide benefitsto subjects suffering from allergies and allergy-related diseases,sinusitis, post-nasal drip, and other medical ailments as describedherein.

In some embodiments, the device works as follows. During inhalation, thefixed cleansing filter 98 or moveable cleansing filter 100 filtersairflow from the external environment before it passes into the airwaysand lungs. During exhalation, in which airflow proceeds from the airwaysand lungs to the outside environment, the fixed cleansing filter 98remains in the path of the airflow, while the moveable cleansing filter100 may deflect or move so that less airflow passes through it (and moreairflow passes around it). In either case, it may be preferable for thecleansing filter not to add any additional resistance to eitherinspiratory or expiratory airflow, though in some cases, that additionof resistance to inspiratory and/or expiratory airflow may be desired.

D. Removable Nostril Opening Application

In one embodiment of the methods for using a respiratory device, thedevice shown in FIG. 22 is placed into one of more of the subject'snostrils by medical personnel or by the subject where it is kept inplace by the subject's nostrils. The device can be worn during the nightor day, while the patient is awake or sleeping. In some cases, thedevice can be worn continuously. In this way, these devices may providebenefits to subjects suffering from sleep apnea, snoring, and othermedical ailments described herein as well as to subjects desiringimproved athletic performance.

In some embodiments, the device works as follows. During inhalation, thedevice props open the nostrils to minimize airflow resistance and toprevent the nostrils from collapsing or partially closing due tonegative pressures within the nose. On exhalation, the devicefacilitates expiratory airflow, again by propping open the nostrils andincreasing the size of the lumen available for airflow.

The respiratory devices may improve the respiratory, cardiac, andgeneral health of the patient by mimicking the effects of pursed-lipbreathing, which is adopted instinctively by many affected patients orby mimicking the expiratory resistance produced by non-invasiveventilation. Physiologically, the devices described herein may providethe same beneficial effects as those experienced in pursed-lipbreathing, specifically: improving oxygen saturation; decreasingrespiratory rate; and increasing tidal volume. The devices may alsoprovide beneficial cardiac effects, including: decreased blood pressure;decreased afterload; decreased preload; decreased heart rate; andimproved ejection fraction. This in turn may reduce the probability ofthe affected patient developing hypertension, heart failure, pulmonaryedema, sleep apnea and other sequelae secondary to chronic obstructivepulmonary disease or heart failure. Furthermore, the devices may offerthe significant advantage of freeing the patient from constantly pursingthe lips, or having to be connected to a non-invasive ventilator via abreathing tube. In contrast to pursed-lip breathing, which cannot beperformed during sleep, and non-invasive ventilation devices that areused primarily at night (and cannot be used during the performance ofdaily activities), these devices may provide increased expiratoryresistance throughout the entire day. Furthermore, respiratory devicesmay be provided for cleansing the inspired air and also for proppingopen the nostrils. These devices represent novel, non-invasive methodsof treating diseases such as allergies, sinusitis, sleep apnea and otherdescribed herein.

All publications and patent applications cited in this specification areherein incorporated by reference in their entirety, as if eachindividual publication or patent application were specifically andindividually indicated to be incorporated by reference. The citation ofany publication is for its disclosure prior to the filing date andshould not be construed as an admission that the present invention isnot entitled to antedate such publication by virtue of prior invention.

Although the foregoing invention has been described in some detail byway of illustration and example for purposes of clarity ofunderstanding, it is readily apparent to those of ordinary skill in theart in light of the teachings of this invention that certain changes andmodifications may be made thereto without departing from the spirit orscope of the appended claims.

1. A nasal respiratory device adapted to be secured at least partiallyover a subject's nose comprising: a nasal mask body configured to besecured at least partially over the subject's nose without covering thesubject's mouth; an airflow resistor coupled to the nasal mask body andconfigured to increase the resistance to air exhaled through the devicemore than the resistance to air inhaled through the device; and aholdfast comprising one or more straps configured to secure the nasalmask body at least partially over the subject's nose.
 2. The nasalrespiratory device of claim 1, wherein the airflow resistor comprises aflap valve.
 3. The nasal respiratory device of claim 1, wherein theairflow resistor is configured to increase the resistance to air exhaledthrough the device when the airflow or the air pressure differentialacross the airflow resistor falls below a threshold level.
 4. The nasalrespiratory device of claim 1, wherein the holdfast further comprises asoft or conformable material to provide a seal to the subject's nose orface to minimize or eliminate air leak around the periphery of the nasalmask body.
 5. The nasal respiratory device of claim 1, wherein the nasalmask body is configured to seal to the subject's nose or face tominimize or eliminate air leak around the periphery of the nasal maskbody.
 6. The nasal respiratory device of claim 1, further comprising asecond airflow resistor coupled to the nasal mask body and configured toincrease the resistance to air exhaled through the device more than theresistance to air inhaled through the device.
 7. The nasal respiratorydevice of claim 1, wherein the nasal mask body is configured to hold theairflow resistor in proximity to the subject's nostrils when the deviceis worn.
 8. The nasal respiratory device of claim 1, wherein the nasalmask body comprises an opening configured to be located over thesubject's nostrils when the device is worn by a subject, further whereinthe airflow resistor is configured to be secured across or within theopening.
 9. The nasal respiratory device of claim 1, wherein the devicecomprises an opening configured to remain open during both inhalationand exhalation.
 10. The nasal respiratory device of claim 1, wherein theairflow resistor comprises an opening configured to remain open duringboth inhalation and exhalation.
 11. The nasal respiratory device ofclaim 1, wherein the device comprises an opening through the nasal maskbody configured to remain open during both inhalation and exhalation.12. A nasal respiratory device adapted to be secured in communicationwith a subject's nasal cavity comprising: a nasal mask body configuredto fit at least partly over the subject's nose without covering thesubject's mouth, the nasal mask body having an opening configured tocommunicate with the nasal cavity; an airflow resistor in communicationwith the opening and configured to increase the resistance to airexhaled through the opening to be more than the resistance to airinhaled through the opening; and a holdfast comprising one or morestraps.
 13. The nasal respiratory device of claim 12, wherein theairflow resistor comprises a flap valve.
 14. The nasal respiratorydevice of claim 12, wherein the airflow resistor is configured toincrease the resistance to air exhaled through the device when theairflow or the air pressure differential across the airflow resistorfalls below a threshold level.
 15. The nasal respiratory device of claim12, wherein the holdfast further comprises a soft or conformablematerial to provide a seal to the subject's nose or face to minimize oreliminate air leak around the periphery of the nasal mask body.
 16. Thenasal respiratory device of claim 12, wherein the nasal mask body isconfigured to seal to the subject's nose or face to minimize oreliminate air leak around the periphery of the nasal mask body.
 17. Thenasal respiratory device of claim 12, further comprising a secondairflow resistor coupled to the nasal mask body and configured toincrease the resistance to air exhaled through the device more than theresistance to air inhaled through the device.
 18. The nasal respiratorydevice of claim 12, wherein the nasal mask body is configured to holdthe airflow resistor in proximity to the subject's nostrils when thedevice is worn.
 19. The nasal respiratory device of claim 12, whereinthe opening is configured to be located over the subject's nostrils whenthe device is worn by a subject, further wherein the airflow resistor isconfigured to be secured across or within the opening.
 20. The nasalrespiratory device of claim 12, wherein the device comprises a secondopening configured to remain open during both inhalation and exhalation.21. The nasal respiratory device of claim 12, wherein the airflowresistor comprises an opening configured to remain open during bothinhalation and exhalation.
 22. The nasal respiratory device of claim 12,wherein the device comprises a second opening through the nasal maskbody, wherein the second opening is configured to remain open duringboth inhalation and exhalation.
 23. A method of inhibiting exhalationthrough the nose more than inhalation through the nose, the methodcomprising: placing a nasal mask at least partially over the subject'snose, wherein the nasal mask comprises a nasal mask body and an airflowresistor coupled to the nasal mask body that is configured to increasethe resistance to air exhaled through the nasal mask more than theresistance to air inhaled through the nasal mask; and securing the nasalmask at least partially over the subject's nose without covering thesubject's mouth.
 24. The method of claim 23, wherein the step ofsecuring comprises sealing the periphery of the nasal mask body to thesubject's nose or face.
 25. The method of claim 23, wherein the step ofsecuring comprises holding the mask to the subject's face using one ormore straps.
 26. The method of claim 23, wherein the step of placing thenasal mask comprises aligning the airflow resistor with one or bothnostrils.
 27. The method of claim 23, further comprising instructing thesubject to wear the mask while sleeping.